- Proper process termination:

if interrupted with CTRL+C blocking socket calls will return with -1. Each device should call FairMQDevice::Shutdown() before ending the running state to close open sockets, otherwise the interrupt call itself will block.

- FIX: Update number of received messages for FairMQFileSink.
- Add ability to poll on outputs for FairMQPoller.

fairmq/nanomsg/FairMQPollerNN.h

@@ -29,6 +29,7 @@ class FairMQPollerNN : public FairMQPoller
 
     virtual void Poll(int timeout);
     virtual bool CheckInput(int index);
+    virtual bool CheckOutput(int index);
 
     virtual ~FairMQPollerNN();