PD: several fixes of shape binder:

* add action to context-menu to remove an element
* use an exclusive button group to avoid to have several buttons pressed at the same time
* allow to completely clear the support
* when pressing OK/Cancel then operate on the document the shape binder is part of (which isn't necessarily the active document)
* remove obsolete parameter from ViewProviderShapeBinder::highlightReferences()

src/Mod/PartDesign/Gui/ViewProviderShapeBinder.cpp

@@ -128,7 +128,7 @@ void ViewProviderShapeBinder::unsetEdit(int ModNum) {
     PartGui::ViewProviderPart::unsetEdit(ModNum);
 }
 
-void ViewProviderShapeBinder::highlightReferences(const bool on, bool /*auxiliary*/)
+void ViewProviderShapeBinder::highlightReferences(bool on)
 {
     App::GeoFeature* obj = nullptr;
     std::vector<std::string> subs;