make MySQL pass our tests under 5.6
Conflicts:
	test/db/mysql/connection_test.rb
handle ("hacked") date/time/timestamp conversion from the JDBC side on 4.2
work done by @prathamesh-sonpatki based on @sgrif's suggestion
appraise latest 4.2
a "fast" attempt to bring 4.2 compatibility to PG but seems it's not the right way

Postgres will be the trickiest to handle multiple AR support with 4.2 ... as always