[IMP]account_m2o: Keep account_m2os editable if mode is edit and make it m2o link when its readonly view, maintained field_manager's list(dfms), if content is destroyed then destroy all dfms, removed edit icon near to account_m2o widget, now user can change account any time in editmode as account_m2os are editable, also fixed some issue raised due to replacement of datejs with moment, like Today in date mode was not working