Part of blueprint common-rpc.
This patch makes the rpc code use the global config object from
openstack-common. Based on some recent discussions on the mailing list,
this may not be the final way configuration handling is done here, but
it is certainly better than the register_opts() hack that is removed by
this patch.
Change-Id: Id128126e0bc064a2a1c710c6bd32fb3d137dc7f6
0f362edeb0