GETCONF allows zero arguments, contrary to spec

control-spec.txt says GETCONF takes at least one argument. Tor currently allows there to be zero arguments for GETCONF. If there are zero arguments, it replies with 250 OK. A reply with a keyword and no = can mean that a configuration variable has its default value. We've therefore committed to having no configuration variables named OK. I suppose that's OK.

Probably the easiest thing to do is to document the existing behavior.