`coqKwdParen` should distinguish `Definition` and its arguments

I also noticed that you can't specify a definition call from its arguments. Example:

Example test_orb1: (orb true false) = true.

orb, true, and false all must be coqKwdParen although they aren't semantically the same. orb is a Definition, and true+false are arguments to the Definition.

Relevant: #87