Distinguish between debug reports for unimplemented vs invalid calls.

Distinguish between debug reports for unimplemented vs invalid calls.

Don't use "fail" in the debug output - as this confuses users.
When reporting on an invalid parameter - use the word "invalid".
When reporting on an unimplemented call - state it is unimplemented.
Add separate debug levels for unimplemented vs invalid calls.
Also, increase the debug level of several entry points.