Revert "Reverting mysql to 0.3.13 due to "undefined symbol" issue during deploy"

This reverts commit 62b110f647cde13b3ce3d76302c134142a27f7f3.
Revert "Upgrade to ruby 2.1.2"

This reverts commit 91fc2d1f54c22b2b2199188545b66afdbe1f12ed, reversing
changes made to 7e8e95b7a3d7c491ff5d56d78a38d654556a9537.