added box-sync to cask packages to be installed
Merge branch 'master' of https://github.com/thegarage/osx-bootstrap into add_box_sync

# By Ryan Sonnek
# Via Ryan Sonnek
* 'master' of https://github.com/thegarage/osx-bootstrap:
  add github hub utility
Merge branch 'add_box_sync'

* add_box_sync:
  added box-sync to cask packages to be installed