[C++] added IMessagingStub.h
[C++] added IMessagingStub.h

this interface will replace the generic IMessaging interface

Change-Id: I1aba459fc940a216fed1a24424a8d266b938f1f3

bmwcarit/joynr,bmwcarit/joynr,bmwcarit/joynr,clive-jevons/joynr,bmwcarit/joynr,clive-jevons/joynr,bmwcarit/joynr,bmwcarit/joynr,clive-jevons/joynr,bmwcarit/joynr,clive-jevons/joynr,bmwcarit/joynr,bmwcarit/joynr,clive-jevons/joynr,clive-jevons/joynr