Port tone equalizer from ART

Merge with local adjustments tone equalizer image processing function
for consistent results.

To-do: Enable for batch editing and add pivot/colormap to the local
adjustments version.

rtgui/toolpanelcoord.h

@@ -78,6 +78,7 @@
 #include "softlight.h"
 #include "spot.h"
 #include "tonecurve.h"
+#include "toneequalizer.h"
 #include "toolbar.h"
 #include "toolpanel.h"
 #include "vibrance.h"
@@ -133,6 +134,7 @@ protected:
     Crop* crop;
     ToneCurve* toneCurve;
     ShadowsHighlights* shadowshighlights;
+    ToneEqualizer* toneEqualizer;
     LocalContrast *localContrast;
     Spot* spot;
     Defringe* defringe;