Version 1.58 released

New in this version:

-Fixed the issue with Spanish governors not gaining priests as their retinue members
-Fixed color of sprites for following mercenary units and their mounts: Thracian Mercenaries, Bastarnae Mercenaries, Sarmatian Mercenaries, Scythian Mercenaries, Spanish Mercenaries, Numidian Mercenaries, Arab Cavalry, Bedouin Warriors, Bedouin Archers and Barbarian Cavalry Mercenaries
-Added unit info picture for spanish Onagers since it was missing