Update ruby-mysql2 to 0.4.4.

Bugfixes

  • Fix segv when num of rows is zero
  • Fix failed to allocate memory for an empty result set
  • Fix :cache_rows => false on prepared statements
  • Fix results buffer allocation fails with prepared statements

Changes

  • Allow repeated each with :cache_rows => false
  • Fix some tests for non-default creds
  • Use the Travis Trusty image for Travis CI

(taca)