Unnecessary import of RoutingContext

In the controller project, the flow service model (sal-flow.yang), the following snippet:

notification node-error-notification {
uses error:error-message;
uses tr:transaction-aware;
uses tr:transaction-metadata;
choice object-reference {
case flow-ref{
leaf flow-ref

{ type types:flow-ref; }

}
case group-ref{
leaf group-ref

{ type group-type:group-ref; }

}
case meter-ref{
leaf meter-ref

{ type meter-type:meter-ref; }

}
}
leaf node

{ ext:context-reference "inv:node-context"; type inv:node-ref; }

}

Results in unused:

import org.opendaylight.yangtools.yang.binding.annotations.RoutingContext;

being emitted in NodeErrorNotificationBuilder. This pollutes eclipse with warnings.