Remove heroku gem dependency
Merge branch 'develop' of github.com:scholarslab/prism into develop

Conflicts:
	Gemfile.lock
Updates the version of rails

Closes security issue for JSON parsing and security vulnerabilities.

closes 105
closes 121
Upgrade Devise

Upgrades Devise to lock it at the 2.2.x version of the gem.
Removes deprecated (and unused) configuration variables
Merge.
Removed the debug information from Twitter. The facebook error was coming from the Facebook settings end of things. Wtih a tweak to redirect url, Facebook now authenticates.