Removed the subforums feature. 
Maybe I'll reimplement this sometime later.
I have removed it because it had many flaws (which I weren't aware) and I can live without this feature. :)
Added ability to create and remove categories.
Renamed the templates for adding and creating users, groups and forums to a more appropriate name.
PEP8 fix and fixed a small bug that prevented the pagination to be generated.
Don't delete the posts and topics a user has created when deleting him.
When deleting the user, we also need to remove him from the other relations.
Fixed a few markread issues
Finally added a command to install flaskbb with a admin user.
Made a many-to-many relation for the moderators.
Rewrapped some lines.
Fixed breadcrumbs; Moved the category layout in another file, so the same file can be used on the index view and categories view.
Various tweaks
Added theming functionality.
Removed unused SQLA types
Moved the permission checks in a new file
Updated README.
I'm not going to support uploading avatars.

There are some really good image hosters available like imgur.com.
We are now able see who has modified the post
Fixed theme changing
The page title is now configureable
Added bootstrap2 theme

Basically just for playing around a bit with flask-themes
Delete the bootstrap2 css file from the static folder