* Removed templated callback overload of NodeImpl::advertiseService()
  as it prevents deduction of the node implementation object type
* Added overloaded versions of NodeImpl::advertiseService() for
  request/response callback signature and service event callback
  signature
* Added empty service server to chatter node for compile-time testing
  of the service-related node implementation members
Merge remote-tracking branch 'origin/master' into remake