Eliminate all fooUnlink() functions out of the API

Eliminate all fooUnlink() functions out of the API
- These are internal helpers only, all refcount users need to use
  fooFree() or similar for correct operation. Add fwd declarations
  where necessary to avoid moving code around unnecessarily.
- We could add these back later as aliases to fooFree() but for now,
  just get them out of the way.