enable components at runtime + grabber refactoring (#160)

* implement enable/disable on runtime for:
- smoothing
- kodi
- udplistener
- boblight

* implement enable/disable for forwarder
refactor component

* - implement grabber enable/disable at runtime
- big grabber refactoring. now with common base class for all grabbers

* implement enable/disable at runtime for bb detector

* osx fix

* try to fix cutted travis output for osx build

include/udplistener/UDPListener.h

@@ -11,6 +11,7 @@
 // Hyperion includes
 #include <hyperion/Hyperion.h>
 #include <utils/Logger.h>
+#include <utils/Components.h>
 
 class UDPClientConnection;
 
@@ -39,6 +40,7 @@ public:
 	/// @return true if server is active (bind to a port)
 	///
 	bool active() { return _isActive; };
+	bool componentState() { return active(); };
 
 public slots:
 	///
@@ -51,6 +53,8 @@ public slots:
 	///
 	void stop();
 
+	void componentStateChanged(const hyperion::Components component, bool enable);
+
 signals:
 	void statusChanged(bool isActive);