Parser priorities2

Don't review it. I'm just trying to test it.
This was actually wrong in the first place.
When you say in the definition:
syntax KLabel ::= "'()"
You want to be able to parse exactly that. And this is why I made the change.

However, it did work before, because the lexical rule for KLabels was imported automatically, and it would have parsed. I only found out recently when I tested it with the new parser, which is a bit cleaner in regard to what it imports.