Made plague-created units have same facing as the dead unit, not random

Technically, they now face the opposite direction than the killer, but in practise it's the same thing since in combat units are always facing each other.

src/actions/attack.cpp

@@ -1155,6 +1155,7 @@ namespace {
 				unit_ptr newunit(new unit(*reanimator, attacker.get_unit().side(), true, unit_race::MALE));
 				newunit->set_attacks(0);
 				newunit->set_movement(0, true);
+				newunit->set_facing(map_location::get_opposite_dir(attacker.get_unit().facing()));
 				// Apply variation
 				if (undead_variation != "null")
 				{