Revert "Downgrading YAML to syck in order to fix 1.9.2 problem, please refer https://github.com/tenderlove/psych/issues/8 for details"
Revert "Downgrading YAML to syck in order to fix 1.9.2 problem, please refer https://github.com/tenderlove/psych/issues/8 for details"

This reverts commit d8c82cdb1fa1b0cacb1bc3777bf9d3d35036a80e.

0xCCD/travis-ci,0xCCD/travis-ci