Added 7 buildings that in the future will be required to purchase mercenaries.
Currently, there will be 8 buildings (one for each era) - the 7 added here plus the Harbor - will be required in a city before any of the future merc units can be added.
There are 4 buildings for merc land units, and 4 for sea.
Exotic Units Pack V2
Adds some unusual units to the game