Enable new callback API

- OnData() channel data handler.
 - ConditionalRun() for devices without incoming data.
 - Header file with common main(), to be extended with getDevice/addCustomOptions.
 - Update examples (MQ/Tutorial3) to use the new API and config.
 - NewSimpleMessage() for simpler creation of small messages (additional copy).
 - Replace SetProperty/GetProperty with fConfig access.
 - Runtime configurable channel names for common devices.
 - Configurable logging interval per channel.
 - FairMQMultiplier for distributing same data to multiple outputs.
 - Cleanup state machine messages.
 - Cmd option to toggle signal handling.
 - Simpler API for send/receive timeouts.
 - Enable --log-to-file.
 - Fix coverity issues, warnings.
 - Various code cleanup and minor tweaks.

examples/MQ/2-sampler-processor-sink/FairMQExample2Sampler.h

@@ -22,25 +22,14 @@
 class FairMQExample2Sampler : public FairMQDevice
 {
   public:
-    enum
-    {
-        Text = FairMQDevice::Last,
-        Last
-    };
     FairMQExample2Sampler();
     virtual ~FairMQExample2Sampler();
 
-    static void CustomCleanup(void* data, void* hint);
-
-    virtual void SetProperty(const int key, const std::string& value);
-    virtual std::string GetProperty(const int key, const std::string& default_ = "");
-    virtual void SetProperty(const int key, const int value);
-    virtual int GetProperty(const int key, const int default_ = 0);
-
   protected:
     std::string fText;
 
-    virtual void Run();
+    virtual void InitTask();
+    virtual bool ConditionalRun();
 };
 
 #endif /* FAIRMQEXAMPLE2SAMPLER_H_ */