RSB II: Punish reckless Counters

Robert will now heal himself prior to Omni if the player tries to use it
as a counterattack opportunity in Phase 4.
Fix stanceChanged event bug, revert RSB II P4

The stanceChanged event invocation was passing the unit reference
instead of the unit's ID.  This broke a few things in Robert's strategy.
Also removed the Counter Stance punishment in Phase 4, as P4 was already
difficult enough without Robert being able to heal too!
RSB II: Make Phase 5 more interesting

Phase 5 as originally conceived was incredibly dull, which is really not
a good thing when it's preceded by a full heal and takes some effort to
prevent it from happening.  So now he uses a ton of magic, with the
average power of his attacks going up as he gets closer to defeat.

Also added some use of Charge Slash by Robert in Phase 2, as that phase
was going by much too quickly, making Phase 3 feel like hitting a brick
wall at 100 mph.