Add enable checkboxes to editor sections

Fixes https://github.com/godotengine/godot-proposals/issues/4173

core/object/object.h

@@ -93,6 +93,7 @@ enum PropertyHint {
 	PROPERTY_HINT_TOOL_BUTTON,
 	PROPERTY_HINT_ONESHOT, ///< the property will be changed by self after setting, such as AudioStreamPlayer.playing, Particles.emitting.
 	PROPERTY_HINT_NO_NODEPATH, /// < this property will not contain a NodePath, regardless of type (Array, Dictionary, List, etc.). Needed for SceneTreeDock.
+	PROPERTY_HINT_GROUP_ENABLE, ///< used to make the property's group checkable. Only use for boolean types.
 	PROPERTY_HINT_MAX,
 };