Add keystone create script for devstack

Add keystone create script for devstack

Copied from heat-keystone-service, with two differences:
The keystone endpoint-create command has been deleted. Devstack uses the
templated catalog driver by default, which does not support this
command. (The equivalent operation is handled manually elsewhere.)

keystone user-role-add parameters have slightly different names,
requiring _id suffixes.

Change-Id: I3d56becde7b6fedbe29e1cfc6a2b4ad9ab2621fa
Signed-off-by: Jeff Peeler <jpeeler@redhat.com>