ENYO-1020: share waitPopup between Ares & Phobos

- Former implementation fires up one, the other one or both without
  a well-defined (or understandable) logic.
- New implementation uses a single Ares#waitPopup that is usable via
  events by any module of Ares.

Enyo-DCO-1.1-Signed-off-by: Francois-Xavier KOWALSKI <francois-xavier.kowalski@hp.com>