install .openrc in the keystone::server recipe

The .openrc file contains useful values for interacting with OpenStack
via the command line such as the keystone service's location and
credentials.

This is being moved from the nova cookbook since there are no nova
specific entries in the file and keystone is higher up in the
barclamp/cookbook dependency chain.
update keystone.conf to Icehouse

- Added a lot of `oslo.messaging` attributes which are unused around
  `amqp`, `rabbitmq`, `kombu`. `rpc_backend` now defaults to rabbitmq instead
  of kombu (but we were never changing this value)

- [auth].methods changed default from `external,password,token,oauth1`
  to `external,password,token`. This was set explicitly in our config,
  but I think it was only because that's how it used to be in Havana as
  we weren't using (or configuring) oauth1.

- A lot of the config options which we were hardcoding are now
  defaults (and commented in the sample config). These were left
  commented like upstream:
  * [auth].password/token/oauth1
  * [catalog].driver
  * [ec2].driver
  * [paste_deploy].config_file
  * [policy].driver
Replaced all license headers with unified layout
Merge pull request #221 from tboerger/feature/license-header

Replaced all license headers with unified layout
Merge pull request #215 from mapleoin/icehouse-configs

update keystone.conf to Icehouse
Merge pull request #214 from mapleoin/openrc

install .openrc in the keystone::server recipe