Bot to check for issues in PR titles

[brettcannon]

Can be a status check to make sure they are formatted correctly.

[brettcannon]

@warsaw has asked this be a status check instead of a bot with a comment to really put it in your face that you forgot an issue number (unless there's a "trivial" label on the PR). This could also be combined with a Misc/NEWS check for #6 since if something required an issue it probably requires a NEWS entry (unless, once again, it's "trivial").

[warsaw]

You'll have to modify some details, but this script might give you a head start.

[brettcannon]

Thanks. I also wrote my own async GitHub library (https://github.com/brettcannon/gidgethub), so I probably can't pull too much from there. 😉

[brettcannon]

I've created https://github.com/python/bedevere that does this check (and will do more things in the future). I will turn it on when I'm not sick and up for watching it for problems.

[brettcannon]

I just turned on Bedevere, so this is now done!