WowAce

Shefki:
    - Deal with being disabled better.
    - Don't depend on a global variable to be unset for normal operation.
    - Fix a typo that would cause an error when healing modifier changed.
    - Cleaner way of avoiding the leaked variable.  Not sure why this didn't
    occur to me last night.
    - Don't leak _
    - Here goes nothing.  First commit should work but untested in a real
    environment.