upgrade the following gems:
sanitize from 3.0.4 to 3.1.0
rouge from 1.7.4 to 1.7.7
better_errors from 2.0.0 to 2.1.0
slim from 3.0.0 to 3.0.1
faye from 1.0.3 to 1.1.0
Merge pull request #32 from NCU-BRATS/upgrade-bundle

upgrade the following gems: