CLC-3592 - Fixed Canvas LTI embedded route. Resolved CookieOverflow issue.
CLC-3592 - Disabled X-Frame-Options header in CanvasLtiController. Added ApplicationController#disable_xframe_options.
Merge pull request #2366 from redconfetti/CLC-3592-resolve-rails4-canvas-lti-integration

CLC-3592 - Resolve Canvas integration issues related to Rails 4 Upgrade