Cut WIP:

+ Added CutObjectBase class which contains cut attributes for object
+ ObjectList and ManipulationPanel :
    * Disable all ManipulationEditors for solid/negative volumes of cut object
    * Disable Scale/Size ManipulationEditors for objects/instances of objects which are CutParts of initial object
+ Scale/Rotation/Move gizmos are disabled for solid/negative volumes of cut object
+ Select whole CutParts of initial object when ScaleGizmo is active

src/slic3r/GUI/GUI_ObjectManipulation.hpp

@@ -57,6 +57,8 @@ public:
     void                set_value(const wxString& new_value);
     void                kill_focus(ObjectManipulation *parent);
 
+    bool                has_opt_key(const std::string& key) { return m_opt_key == key; }
+
 private:
     double              get_value();
 };
@@ -173,6 +175,9 @@ public:
     void        Show(const bool show) override;
     bool        IsShown() override;
     void        UpdateAndShow(const bool show) override;
+    void        Enable(const bool enadle = true);
+    void        Disable() { Enable(false); }
+    void        DisableScale();
     void        update_ui_from_settings();
     bool        use_colors() { return m_use_colors; }