Allow to use flat providernet for public network

The support of ancillary bridges (aka br-ex) is planned to be
dropped for ofagent.  This commit prepares the deprecation by
providing devstack support for an alternative way to connect
public network.

Related to blueprint ofagent-port-monitor
Change-Id: I6c2ce646070db0ed248665216071499a9b5567ab
Exact match rhel6

With rhel6 & rhel7 having a common prefix, use an exact match to make
sure we don't mix them up.  This is breaking Centos7.

Change-Id: Ia4665ea78f0bafeaa2b2284a6d3de4474ea195e9
Cleanup lib/ironic

This moves around a bunch of functionality and attempts to isolate setup
steps into discrete functions (new or existing), making them easier to
consume from outside of Devstack (ie, Grenade).

Change-Id: I480167dcc008506ec2fe8c412db4114b74496e60
Setup AMQP properly for glance-registry

As we integrated OSprofiler with Glance:
https://review.openstack.org/#/c/105635/

glance-registry service started using notification API so it requires
proper seted up AMQP.

Change-Id: I0c4bb8a10960ed3ee06b67a209703d7ee81cf1ca
Merge "Cleanup lib/ironic"
Merge "Allow to use flat providernet for public network"
Remove AUTHORS

AUTHORS isn't really relevant in the days of git.  devstack has no
formal release where it would make sense to auto-generate an AUTHORS
file either.

If you really want to see who contributes, you can run

 $ git log --format='%aN <%aE>' | sort -f | uniq > AUTHORS

Change-Id: I9e154f7fdf814b4bd21a9d4cf82e46ec3db2f1ca
Merge "Exact match rhel6"
Merge "Remove AUTHORS"
Merge "Setup AMQP properly for glance-registry"