Add verbose user repo feed

@bradrydzewski This is the only necessary piece for getting the refreshed drone-wall up to speed on 0.3. @Tathanen is working on getting that side refactored so we can push it out.

I'm open to suggestions on the design since this is a little hamfisted. We basically just need to get the `/api/user/feed` but also including Pending and Started builds. I've done this with an additional `/api/user/feed/verbose` endpoint that also extends the result limit to 20. We do a ton of build traffic at Vokal so the fatter response is something we've found to be necessary.

Indirectly fixes https://github.com/drone/drone-wall/issues/10