Bootstrap Test Suite and Functional Tests for RetailerController

**Summary:**

+ Removes New and Edit Actions

   Since there was no `RetailerController#update`, I completely removed `:edit` and `:new` actions and views. There are some lingering links in other HTML pages that I'll clean up later.

+ Setups a test suite using TestUnit.

    Saw that Rspec was installed, but not being used. I'm more familiar with TestUnit, so I rolled with that today. If you'd like to convert the test suite to Rspec, please let me know - I do want to become better at it.

+ I18n Logic update

    If `:locale` wasn't set in the url and for some weird reason a browser didn't have a language set, then a NoMethod error would be sent. Fixed this and added tests for localization in RetailersController (not sure that's the best place, but works for now). This was fixed so that the test suite would run.

+ Additional details in the commit messages

Please let me know if you have any questions/requests/feedback

Cheers!
Jason