Upgrade to Ruby 2.1.1 and Rails 4.0.3

The transition was clean, except for CanCan not having official support for Strong Parameters. Added a [simple hack](https://github.com/ResourceDataInc/commuter_challenge/blob/70cae4e818eb291d05904d548fef016cd501d45d/app/controllers/application_controller.rb#L29-L33) for now, but it would be nice to not have to make this check for [every request](https://github.com/ResourceDataInc/commuter_challenge/blob/70cae4e818eb291d05904d548fef016cd501d45d/app/controllers/application_controller.rb#L5) that comes through.