Revert "Merge pull request #254 from abrody/master"

This reverts commit 3ac7d82951a955b310c87db673ae0992432581b5, reversing
changes made to 5098c81d66ee15d4be60ee9acc81297a80f400ac.
Reduce connect_timeout by elapsed time when retrying.

If a signal interrupts mysql_real_connect, then using the original
connect_timeout would allow the connect method to take longer than
connect_timeout, so reduce by the elapsed time.
Add a default connect_timeout option of 2 minutes.
Merge pull request #505 from dylanahsmith/fix-eintr-retry

Fix connect retry on interrupt and connection timeout