py_enemy_turret 80% done

Turret now places itself correctly, fires (& in the correct direction),
and has two editor enums: 'Where to fire' and 'Where it's wall is'. Once
selected within the editor, everything else is taken care of.

From here on out, all I need to do is attach Travis' two sprites and
have them attach themselves correctly.
Updated py_enemy_turret 90% done

Angle and placement re-worked. Need to add death info.
Made Turret an Archtype
committing... nothing?