monster use phases

Leap of faith hoping everything works.

- now monsters' actions also get split between different phases.
- the monster can only move OR attack in the same phase.
- if the monster moves and has points left to attack on next phase, the
next phase is populated.
- fix for initiative when previously hidden monsters become visible, and
so have to roll initiative on next turn.

One issue is that a monster can use all its movement points in his
phase, instead of half.