Ninjas can now phase jaunt.

Adds Phase Jaunt for a cost of 250 energy, compared to Phase Shift which costs 400E.
Randomly jumps the ninja 5-9 tiles straight ahead. Does not harm any creature in the way.
Adds cooldown to Phase Shift.

Cell power is now reduced directly in the ninjacost() proc.
Some cleanup of ninja verb-add/removal.

Based on #6311.