Make os-services API extension consistent

Make os-services API extension consistent

Updates the os-services API extension so that it is consistent
internally (index and update return similar formats), and so
that it works with the following cinderclient code changes which sends
the the following request body format:

  {"binary": "cinder-volume", "host": "host1"}

It addresses a similar issue which happens in nova os-services extention
before. https://bugs.launchpad.net/nova/+bug/1147746

This change added 'binary' key in request and 'status' key in response
while still keeping 'service' ane 'disabled' key for API compatibility
sake.

Implements blueprint os-services-extension

Change-Id: I7f3fa889294ca6caebdf46b8689345bcac1cdf54