Age Restricted Thread Prefixes

Restrict young users from viewing or posting threads with a certain prefix.

Description
- Makes users below a certain age unable to view threads with a certain prefix, depending on the forum.
- Makes users below a certain age unable to create threads with a certain prefix, depending on the forum.
- Age is calculated from birthday options. If these are not set in the user account, a prompt will show up in order to know whether the user wants to change his birthday. (See image at mods center)

Configuration options:
- IDs of prefixes that require a certain age. (Comma separated)
- Forum IDs in which this plugin is active
- Minimum age to view or post using prefix(es)
- A few language options