Using forward declaration when possible

src/Renderer/GenericRenderer.h

@@ -27,10 +27,13 @@
 #include <QWidget>
 #include <QLabel>
 
-#include "Clip.h"
 #include "VLCMediaPlayer.h"
 #include "MainWorkflow.h"
 
+class   Clip;
+class   Media;
+class   QUuid;
+
 /**
  *  \class  Common base for every renderer.
  */