MindMap: partial implementation

Conflicts:
	org.flowerplatform.editor.model/flex_src/org/flowerplatform/editor/model/DiagramEditorFrontend.as
	org.flowerplatform.editor.model/flex_src/org/flowerplatform/editor/model/remote/DiagramEditorStatefulClient.as
	org.flowerplatform.web/launch_configs/Flower Platform - Web.launch
Restored methods removed at merge in DiagramEditorStatefulClient
Editor: switch to open editor + open editors list on mobile
Merge remote-tracking branch 'origin/master' into editor_migration