Archives 84 rb

* [x] Route for `/ideas/archives => IdeaThreadsController#archives`
* [x] Update IdeaThreadCollectionView to only apply archive filter on the dashboard, not the archive page
* [x] Don't show archived link on Archived IdeaThreads
* [x] Disabling voting on Archived threads.
   * Refactor of the actual voting method. Moved out of view into
  Idea Model to do the check. VotesCollection actually creates
  the vote. Cleans up view considerably.
  * Checks IdeaThread's status before adding or removing a vote.