Add new "-q" logging option (quiet mode) while in initialize mode

Add new "-q" logging option (quiet mode) while in initialize mode
(-i), producing only one progress message per 5 seconds along with
elapsed time and estimated remaining time.  Also add elapsed time and
estimated remaining time to the default logging(prints one message
each 100000 rows).
Patch contributed by Tomas Vondra, reviewed by Jeevan Chalke and
Tatsuo Ishii.