Updated implementation of internal RPC Router for Binding-Aware Broker and added...

Updated implementation of internal RPC Router for Binding-Aware Broker and added IT to it

sal-binding-broker:
    Updated implementation of runtime code generator to adhere to RpcRouter contract,
    which is used by binding aware broker for introspection and configuration of runtime generated
    instances without need to use Reflection.

sal-binding-it:
    Added end-to-end integration test which tests following scenarios:
      - Registration of 2 Providers of Flow Service, 1 Consumer
        after registration 4 instances of Flow Service are existing:
         MD-SAL Northbound (runtime generated) - returned to the consumer.
         Optimized RpcRouter (runtime generated) - internal to MD-SAL
         2 implementations supplied by Provider.

      - Test verifies that implementations are not leaked to the Consumer

      - Routing of messages (calls):
         1. Provider 1. registers as provider for Node One, Consumer sends message to Node One, Provider 1. is invoked.
         2. Provider 2. registers as provider for Node Rwo, consumer sends message to Node Two, Provider 2. is invoked.
	 3. Provider 1. unregisters as provider for Node One, Provider 2. registers as provider  for Node One,
            Consumer sends message to Node One, Provider 2. is invoked.

Change-Id: I101e26c190cd1770aaff1db974f9b0c341506482
Signed-off-by: Tony Tkacik <ttkacik@cisco.com>