Add rackspace specific clients

All of the rackspace resources are using custom client implementations
that override the openstack clients via inheritance. This method is
not great because it does not override clients system wide. Add the
custom clients.py and migrate away from the rackspace_resource.

Change-Id: I796e6e0050b4d8e3829d82bc5d3e179110c281c1
change pyrax client functions

Change-Id: I9e93d093ab79d34b07664ea0ad0ef42abbaa87c2
fix pyrax

Change-Id: If2d45bc860c2ede180133afde0cdd88b39006eb3
merge rackspace resources

Change-Id: I9029ab4066187319773d822650b11961f9b0a8fe