Use GitHub Status API

[Fishrock123]

Here's a test of a success status, and a failure status.

cc @williamkapke & @phillipj

[Fishrock123]

Fixes: #14

[Fishrock123]

rebased

[williamkapke]

LGTM

[phillipj]

You mentioned on IRC that we should be polling SHA for all repos. Any reason you haven't deleted pollByPrThenComment()?

IIRC this means we would do status updates for readable-stream, but still do comments on nodejs.org and citgm.

[phillipj]

Have you tested updates on PRs and how that affects previously set statuses? Could we end up with misleading success status on a PR if the first build succeeded, but new commits/pushed rebase results in brokens builds?

[Fishrock123]

@phillipj I left that because I wasn't sure if it was still necessary.

Afaik statuses tie to commits, so if the commits are updated GitHub automatically resets it.

[Fishrock123]

I'll give it a test when I get home later though.

[Fishrock123]

Hmmm, looks like this no-longer works after being rebased on #8. Investigating.

[Fishrock123]

Got it working. My bad.

Looks like this doesn't actually handle PR updates, working on it. (Example: TestOrgPleaseIgnore/test-github-bot#17)

[Fishrock123]

Updated, now works for PR updates: TestOrgPleaseIgnore/test-github-bot#17

[Fishrock123]

going to open a new PR for some of the other bits