Updated Propify! Ghost Fix

Added precise checks for model paths.
Updated Propify!

Added forwards to let plugins know that a prop was added or removed from
the list.
Updated Propify! plugins

Added "Propify_" prefix to all external-facing methods while we were
adding new methods.  I NEVER KNEW PLUGIN CONVENTIONS WERE SO HARD

Bumped Propify! up a version number; the others are just patch
revisions.