Fixed meta collector not applying mappings
Fixed meta collector not applying mappings

Meta collector wasn't applying service to collector mapping at all.
Removed attributes checking on tested collectors. Retrieve is the
interfaces for this.

Change-Id: Id5f35571e2585db1dd123be6a5172c98797f4f21
Depends-On: I20ba915175bce5dcda72fbfd449770c72b91fce0

muraliselva10/cloudkitty,stackforge/cloudkitty,openstack/cloudkitty,muraliselva10/cloudkitty,openstack/cloudkitty,stackforge/cloudkitty