ENYO-2799: Fixed onyx.DatePicker fails to be re-rendered by the Designer after modifyProperty

Needs https://github.com/enyojs/ares-project/pull/459

Enyo-DCO-1.1-Signed-off-by: Yves Del Medico <yves.del-medico@hp.com>
Merge pull request #4 from hp-ws/ENYO-2799

ENYO-2799: Fixed onyx.DatePicker fails to be re-rendered by the Designer...