Added CloudKitty developer documentation
Added CloudKitty developer documentation

Change-Id: I09b9fafa7bea9c8b82118507eeaac95340c0b5a5
Depends-On: I1500efe757dd262035aaf26e586386da5a0e9081

openstack/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,AlekhyaMallina-Vedams/openstack-manuals,openstack/openstack-manuals