[OzzModz] Force Rules Accept For Threads - XF2 2.0.0

This addon just adds a checkbox "I have read and accepted the forum rules" with a link to rules while posting a thread.
This can be used for forcing users read rules for specific forums before creating a thread. The "Post thread" button for saving a thread is disabled when the checkbox is not checked. The "Post thread" button for saving a thread will become active once the user checks the checkbox. The rules URL is set per forum directly in adding/editing a forum.