Post Delete Time Limit 2.2.0

Permission to limit how old a post/thread can be and still be deleted, separate from the stock XenForo edit time window permission

Introduces 1 new permissions:

• Time limit on deleting own messages (minutes) (default 0, never can delete)

Note; delete any post will bypass this permission.

Contributing features or bug fixes
Please create a Github Pull request via the "More information" link.