Refactor Navigation Cube

-Use std commands in menu coming with icons
-Only draggable if activated in menu
-Remove textures except labels and used gl fill instead
-Borders on surrounding buttons
-Fix some openGL issues
-Remove duplicate parameter managment. Kept and improved the one in View3DSettings
-Remove lots of other redundant code
-Replaced FontSize param with FontZoom and enabled auto zoom/size on labels.
-Merged BorderColor and TextColor to single EmphaseColor parameter
-Merged ButtonColor and FrontColor to BaseColor parameter
-Added ChamferSize parameter to control edge and corner size
-Use glDrawArrays() innstead of glBegin() and glEnd()
-Draw butt ends on RGB coordinate system
-Fixe issues where cube switch corner on resize window

src/Gui/View3DInventor.cpp

@@ -145,7 +145,6 @@ View3DInventor::~View3DInventor()
     }
 
     viewSettings.reset();
-    naviSettings.reset();
 
     //If we destroy this viewer by calling 'delete' directly the focus proxy widget which is defined
     //by a widget in SoQtViewer isn't reset. This widget becomes a dangling pointer and makes