trying to implement colllaboratoration
created collaborator controller and model
updated seeds.rb file, wiki and collaborator models
further upgrading collaboration
dropped articles table and updated seeds.rb
cleaned up remaining files mentioning article.
updating controllers
added users to collaborators and cleaned up the rest of the code
updated collab and wiki controller and collab index view.
updated ability.rb to allow collab to view and edit
Merge pull request #29 from 3B7/collborators

trying to implement colllaboratoration