added haze removal tool

Based on the paper:
  "Single Image Haze Removal Using Dark Channel Prior" by He, Sun and Tang
using a guided filter for the "soft matting" of the transmission map

rtgui/toolpanelcoord.h

@@ -80,6 +80,7 @@
 #include "fattaltonemap.h"
 #include "localcontrast.h"
 #include "softlight.h"
+#include "dehaze.h"
 #include "guiutils.h"
 
 class ImageEditorCoordinator;
@@ -136,6 +137,7 @@ protected:
     DirPyrEqualizer* dirpyrequalizer;
     HSVEqualizer* hsvequalizer;
     SoftLight *softlight;
+    Dehaze *dehaze;
     FilmSimulation *filmSimulation;
     SensorBayer * sensorbayer;
     SensorXTrans * sensorxtrans;