* Added `user_id` and `forum_id` as indicies to the `forum_moderations` table.
* Added `user_id` and `category_id` as indicies to the `category_moderations` table.
* Added thread reading and writing functionality.
* Added comment writing functionality (All comment logic is in Forum::Thread controller).
* `control_box` partial displays a row of buttons that refers to a thread. (Dummy buttons for now)
* Updated `user_*` partials to use a better syntax.
* Main site layout now uses the 'breadcrumb' partial.