Add $ prefix (comes after - and #) to make PEX interpret the following permission as a raw regex and not do any conversion
Remove duplicate inheritance changed event call
Optimize permission registration with superperms

A few tactics:
1. Add permissions as children to a single permission which is then
added to the attachment, instead adding each permission directly. This
allows to only recalculate permissions (an expensize task) once,
rather than after adding each permission directly.
2. Depending on the type of event called, only update either the
permissions or the metadata, not both. This prevents collecting the
player's permissions or options unnecessarily.
Add visited groups tracker

This will prevent duplicate visits to inherited groups (and therfore
circular inheritance)
However, it prevents circular inheritance silently. I'd put a warning on
this when a duplicate group is encountered, but there are legitimate
cases where this can happen.

Fixes #912