Update Rails to 4.1

Summary of changes:

* Updated to Rails 4.1 to use AR Enums and Spring.
* Bumped TravisCI Ruby version to 2.1.1. Added Spring gem to development and test environments.
* Removed deprecated stub method.
* Small routes.rb fix.
* Using ActiveRecord Enums from Rails 4.1 for User status. Users are either registered or active and to be used in conjunction with new payments feature. Users are registered by default and are active once they have paid the current year's dues.

Unlike #154, this can be merged in at anytime.