Allow regular (non-admin) users access to the Manage Forums page so they can
create and manage their own forums.
Things that were already working:
* The admin forum page was already anticipating regular LoginRequired credential
* Users only see their owned forums, while admins can see and manage ALL forums
Improvements made to the Forum Admin page:
* Change the title color from admin-red to user-blue.
* Add ability to search (filter) and sort the forums.
Other changes:
* Turn the Forum tab bar into a reusable component.
Adds initial code for basically functional forums:
* Forums landing page shows hard-coded list of Categories along with any
forums in the DB that use those categories.
* Admin: Create, Edit forums and view forums you own or have admin rights
to modify.
* Landing page forums list shows the title/description and dynamic count of
number of Topics and total number of Posts in each forum. TODO: distinct
count of Users who posted in each forum.
* Board Index page shows list of Threads (posts) with a Replies count and
Views count on each thread.
* Thread view is basically an array of Comments. Users can post, edit and
delete (their own) comments. Deleting the first comment removes the
entire Thread - the thread points to a first Comment to provide its body.
* Reply and Quote-Reply options working.
