Support No-Ticket branches

[ryanfreckleton]

Occasionally we have to do changes that aren't associated with a work ticket. It would be nice if GPT would accept no-ticket branches and commits instead of having to hit --no-verify on them.

[toddjtidwell]

You should always have a ticket :P

[toddjtidwell]

However, I can see that not everyone would allow that. I'll see about some sort of flag you can use or something.