ENYO-3677: ENYO-3629: reindented for ENYO-3311
ENYO-3677: ENYO-3629: lang.js added assertCb and noNext function
ENYO-3677: handle mandatory next callbacks
Merge pull request #719 from enyojs/ENYO-3677

ENYO-3677: added required next() to fix/undo/redo