Patch from issue 1359: "Munsell correction - Lab adjustements" credits: jdesmis

Bundled new features besid the Lab tool enhancement (by jdesmis) :
   - curve to control skin tones in vibrance tool, credits: jdesmis
   - right click over SHCSelector (below the parametric curve) to reset to default values, credits: Hombre
   - colored bars around curves, credits: Hombre

rtengine/init.cc

@@ -43,7 +43,6 @@ int init (const Settings* s, Glib::ustring baseDir) {
     profileStore.init ();
     ProcParams::init ();
     Color::init();
-    ImProcFunctions::initMunsell();
     ImProcFunctions::initCache ();
     Thumbnail::initGamma ();
     delete lcmsMutex;