Tagmata

added new faction, Tagmata, byzantine style bow lancers and armored horse archers and skutatoi

added whole new unit type, skutatoi, where the front ranks hold spears and the rear shoot, half shooting power of bowmen, passive spears type unit.

added new visuals for armored horse archers (need better byzantine style armor models though)

various bug fixes 

minor ai and deployment changes for cavalry heavy armies. some pursuit/evade/rout changes, some goadable shooting changes (more random and not from so long a distance)