Slow down Saurian magic animation.
Anims use unit objects as of construct time.

Take all units by value so the unit state doesn't change between the
time when the animation is created and when it runs.
Spells that target self shouldn't change facing.
Removed an unnecessary variable.
Add borders to make space for a unit display.
Convert traits to a comma-delimited string.
Support empty strings when drawing text.
New display for the active unit.