docs: ulink all references to RFC's

Make sure that the first mentions of RFC's are ulinked to their ietf.org
entry, and subsequent ones are marked as acronyms. This makes references
to RFC's consistent across the documentation.

Author: Daniel Gustafsson
Discussion: https://www.postgresql.org/message-id/2C697878-4D01-4F06-8312-2FEDE931E973%40yesql.se

Author: hlinnaka

doc/src/sgml/catalogs.sgml

@@ -1598,7 +1598,7 @@ SCRAM-SHA-256$<replaceable>&lt;iteration count&gt;</replaceable>:<replaceable>&l
 </synopsis>
    where <replaceable>salt</replaceable>, <replaceable>StoredKey</replaceable> and
    <replaceable>ServerKey</replaceable> are in Base64 encoded format. This format is
-   the same as that specified by RFC 5803.
+   the same as that specified by <ulink url="https://tools.ietf.org/html/rfc5803">RFC 5803</ulink>.
   </para>
 
   <para>

doc/src/sgml/charset.sgml

@@ -2663,7 +2663,7 @@ RESET client_encoding;
       </varlistentry>
 
       <varlistentry>
-       <term>RFC 3629</term>
+       <term><ulink url="https://tools.ietf.org/html/rfc3629">RFC 3629</ulink></term>
 
        <listitem>
         <para>

doc/src/sgml/client-auth.sgml

@@ -948,7 +948,8 @@ omicron         bryanh                  guest1
     <listitem>
      <para>
       <link linkend="auth-ident">Ident authentication</link>, which
-      relies on an <quote>Identification Protocol</quote> (RFC 1413)
+      relies on an <quote>Identification Protocol</quote>
+      (<ulink url="https://tools.ietf.org/html/rfc1413">RFC 1413</ulink>)
       service on the client's machine.  (On local Unix-socket connections,
       this is treated as peer authentication.)
      </para>
@@ -1198,7 +1199,8 @@ omicron         bryanh                  guest1
 
    <para>
     <productname>GSSAPI</productname> is an industry-standard protocol
-    for secure authentication defined in RFC 2743.
+    for secure authentication defined in
+    <ulink url="https://tools.ietf.org/html/rfc2743">RFC 2743</ulink>.
 
     <productname>PostgreSQL</productname>
     supports <productname>GSSAPI</productname> for use as either an encrypted,
@@ -1503,7 +1505,8 @@ omicron         bryanh                  guest1
 
    <para>
     The <quote>Identification Protocol</quote> is described in
-    RFC 1413. Virtually every Unix-like
+    <ulink url="https://tools.ietf.org/html/rfc1413">RFC 1413</ulink>.
+    Virtually every Unix-like
     operating system ships with an ident server that listens on TCP
     port 113 by default. The basic functionality of an ident server
     is to answer questions like <quote>What user initiated the
@@ -1671,8 +1674,8 @@ omicron         bryanh                  guest1
        <para>
         Set to 1 to make the connection between PostgreSQL and the LDAP server
         use TLS encryption.  This uses the <literal>StartTLS</literal>
-        operation per RFC 4513.  See also the <literal>ldapscheme</literal>
-        option for an alternative.
+        operation per <ulink url="https://tools.ietf.org/html/rfc4513">RFC 4513</ulink>.
+        See also the <literal>ldapscheme</literal> option for an alternative.
        </para>
       </listitem>
      </varlistentry>
@@ -1766,7 +1769,8 @@ omicron         bryanh                  guest1
        <term><literal>ldapurl</literal></term>
        <listitem>
         <para>
-         An RFC 4516 LDAP URL.  This is an alternative way to write some of the
+         An <ulink url="https://tools.ietf.org/html/rfc4516">RFC 4516</ulink>
+         LDAP URL.  This is an alternative way to write some of the
          other LDAP options in a more compact and standard form.  The format is
 <synopsis>
 ldap[s]://<replaceable>host</replaceable>[:<replaceable>port</replaceable>]/<replaceable>basedn</replaceable>[?[<replaceable>attribute</replaceable>][?[<replaceable>scope</replaceable>][?[<replaceable>filter</replaceable>]]]]
@@ -1827,7 +1831,8 @@ ldap[s]://<replaceable>host</replaceable>[:<replaceable>port</replaceable>]/<rep
      If <productname>PostgreSQL</productname> was compiled with
      <productname>OpenLDAP</productname> as the LDAP client library, the
      <literal>ldapserver</literal> setting may be omitted.  In that case, a
-     list of host names and ports is looked up via RFC 2782 DNS SRV records.
+     list of host names and ports is looked up via
+     <ulink url="https://tools.ietf.org/html/rfc2782">RFC 2782</ulink> DNS SRV records.
      The name <literal>_ldap._tcp.DOMAIN</literal> is looked up, where
      <literal>DOMAIN</literal> is extracted from <literal>ldapbasedn</literal>.
    </para>

doc/src/sgml/datatype.sgml

@@ -2384,7 +2384,8 @@ TIMESTAMP WITH TIME ZONE '2004-10-19 10:23:54+02'
       ISO 8601 specifies the use of uppercase letter <literal>T</literal> to separate
       the date and time.  <productname>PostgreSQL</productname> accepts that format on
       input, but on output it uses a space rather than <literal>T</literal>, as shown
-      above.  This is for readability and for consistency with RFC 3339 as
+      above.  This is for readability and for consistency with
+      <ulink url="https://tools.ietf.org/html/rfc3339">RFC 3339</ulink> as
       well as some other database systems.
      </para>
     </note>
@@ -4247,7 +4248,8 @@ SELECT to_tsvector( 'postgraduate' ), to_tsquery( 'postgres:*' );
 
    <para>
     The data type <type>uuid</type> stores Universally Unique Identifiers
-    (UUID) as defined by RFC 4122, ISO/IEC 9834-8:2005, and related standards.
+    (UUID) as defined by <ulink url="https://tools.ietf.org/html/rfc4122">RFC 4122</ulink>,
+    ISO/IEC 9834-8:2005, and related standards.
     (Some systems refer to this data type as a globally unique identifier, or
     GUID,<indexterm><primary>GUID</primary></indexterm> instead.)  This
     identifier is a 128-bit quantity that is generated by an algorithm chosen

doc/src/sgml/ecpg.sgml

@@ -3226,7 +3226,7 @@ int PGTYPEStimestamp_fmt_asc(timestamp *ts, char *output, int str_len, char *fmt
            <literal>%z</literal> - is replaced by the time zone offset from
            UTC; a leading plus sign stands for east of UTC, a minus sign for
            west of UTC, hours and minutes follow with two digits each and no
-           delimiter between them (common form for RFC 822 date headers).
+           delimiter between them (common form for <ulink url="https://tools.ietf.org/html/rfc822">RFC 822</ulink> date headers).
           </para>
          </listitem>
          <listitem>

doc/src/sgml/func.sgml

@@ -4449,7 +4449,7 @@ SELECT format('Testing %3$s, %2$s, %s', 'one', 'two', 'three');
       <para>
        The <literal>base64</literal> format is that
        of <ulink url="https://tools.ietf.org/html/rfc2045#section-6.8">RFC
-       2045 Section 6.8</ulink>.  As per the RFC, encoded lines are
+       2045 Section 6.8</ulink>.  As per the <acronym>RFC</acronym>, encoded lines are
        broken at 76 characters.  However instead of the MIME CRLF
        end-of-line marker, only a newline is used for end-of-line.
        The <function>decode</function> function ignores carriage-return,

doc/src/sgml/json.sgml

@@ -61,7 +61,7 @@
  </para>
 
  <para>
-  RFC 7159 specifies that JSON strings should be encoded in UTF8.
+  <acronym>RFC</acronym> 7159 specifies that JSON strings should be encoded in UTF8.
   It is therefore not possible for the JSON
   types to conform rigidly to the JSON specification unless the database
   encoding is UTF8. Attempts to directly include characters that
@@ -71,7 +71,7 @@
  </para>
 
  <para>
-  RFC 7159 permits JSON strings to contain Unicode escape sequences
+  <acronym>RFC</acronym> 7159 permits JSON strings to contain Unicode escape sequences
   denoted by <literal>\u<replaceable>XXXX</replaceable></literal>.  In the input
   function for the <type>json</type> type, Unicode escapes are allowed
   regardless of the database encoding, and are checked only for syntactic

doc/src/sgml/libpq.sgml

@@ -7462,8 +7462,9 @@ user=admin
    <literal>ldap://</literal> will be recognized as an LDAP URL and an
    LDAP query will be performed. The result must be a list of
    <literal>keyword = value</literal> pairs which will be used to set
-   connection options.  The URL must conform to RFC 1959 and be of the
-   form
+   connection options.  The URL must conform to
+   <ulink url="https://tools.ietf.org/html/rfc1959">RFC 1959</ulink>
+   and be of the form
 <synopsis>
 ldap://[<replaceable>hostname</replaceable>[:<replaceable>port</replaceable>]]/<replaceable>search_base</replaceable>?<replaceable>attribute</replaceable>?<replaceable>search_scope</replaceable>?<replaceable>filter</replaceable>
 </synopsis>

doc/src/sgml/pgcrypto.sgml

@@ -437,7 +437,8 @@ gen_salt(type text [, iter_count integer ]) returns text
   <title>PGP Encryption Functions</title>
 
   <para>
-   The functions here implement the encryption part of the OpenPGP (RFC 4880)
+   The functions here implement the encryption part of the OpenPGP
+   (<ulink url="https://tools.ietf.org/html/rfc4880">RFC 4880</ulink>)
    standard.  Supported are both symmetric-key and public-key encryption.
   </para>
 
@@ -806,7 +807,7 @@ Applies to: pgp_sym_encrypt, pgp_pub_encrypt
    <para>
     Whether to convert <literal>\n</literal> into <literal>\r\n</literal> when
     encrypting and <literal>\r\n</literal> to <literal>\n</literal> when
-    decrypting.  RFC 4880 specifies that text data should be stored using
+    decrypting.  <acronym>RFC</acronym> 4880 specifies that text data should be stored using
     <literal>\r\n</literal> line-feeds.  Use this to get fully RFC-compliant
     behavior.
    </para>
@@ -823,7 +824,7 @@ Applies to: pgp_sym_encrypt, pgp_pub_encrypt, pgp_sym_decrypt, pgp_pub_decrypt
    <para>
     Do not protect data with SHA-1.  The only good reason to use this
     option is to achieve compatibility with ancient PGP products, predating
-    the addition of SHA-1 protected packets to RFC 4880.
+    the addition of SHA-1 protected packets to <acronym>RFC</acronym> 4880.
     Recent gnupg.org and pgp.com software supports it fine.
    </para>
 <literallayout>

doc/src/sgml/protocol.sgml

@@ -1501,7 +1501,8 @@ SELCT 1/0;<!-- this typo is intentional -->
     is willing or unwilling to perform <acronym>GSSAPI</acronym> encryption,
     respectively.  The frontend might close the connection at this point
     if it is dissatisfied with the response.  To continue after
-    <literal>G</literal>, using the GSSAPI C bindings as discussed in RFC2744
+    <literal>G</literal>, using the GSSAPI C bindings as discussed in
+    <ulink url="https://tools.ietf.org/html/rfc2744">RFC 2744</ulink>
     or equivalent, perform a <acronym>GSSAPI</acronym> initialization by
     calling <function>gss_init_sec_context()</function> in a loop and sending
     the result to the server, starting with an empty input and then with each
@@ -1616,7 +1617,8 @@ ErrorMessage.
    The implemented SASL mechanisms at the moment
    are <literal>SCRAM-SHA-256</literal> and its variant with channel
    binding <literal>SCRAM-SHA-256-PLUS</literal>. They are described in
-   detail in RFC 7677 and RFC 5802.
+   detail in <ulink url="https://tools.ietf.org/html/rfc7677">RFC 7677</ulink>
+   and <ulink url="https://tools.ietf.org/html/rfc5802">RFC 5802</ulink>.
   </para>
 
   <para>