A new Designate service to be run on a DNS master that is the 'reflection' of
MiniDNS. It receives Create/NOTIFY/Delete actions, and calls into a backend
that greatly resembles the style of backends in Designate before Server Pools.
This is a squashed commit that formerly contained the following 'Agent' topics:
Basic Service
Add basic NOTIFY support
Add AXFR Capability
Add Support for Receiving Private CLASS/RRDATA Messages
Add Backend Capabilities
Cleanup (Changes here: http://paste.openstack.org/show/160022/)
Implements: blueprint new-agent
Change-Id: I610687878be9dee8065ebc492f662e86bbeb8ce7