Track and post #job-board stats

[vcarl]

Probably blocked by having the ability to store state, so we don't have to crawl the server on startup to build recent historical data. We've had a recurring survey posted for a long time; it would be an improvement if folks could indicate more exactly which jobs they applied for/got. If we could say, like, "this week 5 jobs were posted, 50 people reported applying a total of 200 times, and 3 people reported that they found work here", I think it'd be a really good way of surfacing how well it's working for people