BUG-7608: Add ActionServiceMetadata and ActionProviderBean

BUG-7608: Add ActionServiceMetadata and ActionProviderBean

This patch add the new concepts of action-provider and
action-service.

The implementation does nothing, as we are transitioning from
a run-time logic being coupled with sal-remoterpc-connector.

This allows us to migrate users, while retaining behavior indepent
of sal-remoterpc-connector's actions. This will allow us to fix
BUG-3128.

Once it is fixed, and DOMRpcRouter can express the action-provider
advertisement, we are going to actiovate the commented-out code
ActionServiceMetadata.acceptableStrategy().

Change-Id: I3f412d092c10b51a198721f288fdefdfc907f0b7
Signed-off-by: Robert Varga <rovarga@cisco.com>