ENYO-2978: Undo/Redo improvement by limiting goes and returns between Phobos and Deimos, de/reactivation of buttons during undo/redo updates
ENYO-2978: undo/redo capability checking improvement
ENYO-2978: dead code removing
Merge branch 'ENYO-3023' into ENYO-2978

Conflicts:
	deimos/source/Deimos.js
ENYO-2978: really remove dead code
ENYO-2978: code improvement
ENYO-2978: rename methode provideButtons to enableDesignerActionButtons
Revert "ENYO-2978: code improvement"

This reverts commit bd7f55dfa027c5f40bac6a985687b9247f452ac4.
ENYO-2978: avoid special data case discradind
ENYO-2978: clarified comment
Merge pull request #533 from enyojs/ENYO-2978

ENYO-2978: Designer undo/redo improvements