Change from HABTM to HMT with Collaborations model (may become polymorphic later if needed). Update view so sharing and unsharing of individual users works. Currently does not use Ajax.
Clean up temporary files.
Fix bugs in User model for HMT association. Write simple authorization logic from scratch and confirm that editing from multiple users works and commits correctly. Modify commit method in Wiki model to allow passing in the current user. Attempt to write something in Cancan's Ability class but so far not using it.