Update ETFlex to Rails 4.1

Other noteworthy changes (this one was a bit of a pain):

  * Removed the unused `UsersController` and references to OmniAuth which were raising errors.
  * shoulda-matchers no longer required in the Gemfile, since doing so outputs messages about minitest.
  * Default scope removed from Scenario, and added it explicitly to the few places which need it.
  * Admin actions now use strong_parameters since `attr_accessible` has been removed in Rails 4.1. I was sure I did this as part of the update to Rails 4.0, but apparently not? :confused:
  * Fixed bad indentation in the "tour.coffee" file which prevented compilation in the newer version of CS.
  * Updated Haml from 3.1 to 4.0.
  * Updated simple_form from 2.1 to 3.0.