Remove $fh.feed from fh-mbaas-api

As the reaper is not running in the cheffed clusters, the $fh.feed api in fh-mbaas-api is a broken api. It is no longer documented in our developer docs, but the code still exists. We should remove this code.
The reaper was removed from millicore recently.

The code lives here:
https://github.com/feedhenry/fh-mbaas-api/blob/master/lib/feed.js

We will need to update the template apps too with the new version of fh-mbaas-api