I was wrong about there only ever being a single Comment and/or Downtime object.  If there are multiple Comment or Downtime objects, we need to see them.
Added support for multiple Comment and Downtime objects to be returned by http_host.
Merge pull request #32 from RyanFrantz/master

I thought I was introducing an optimization be ensuring we didn't needlessly loop over multiple keys. Turns out, I introduced a bug that prevents the API from seeing multiple downtimes for a given host.