-City Walls art updated
-Walls of Babylon back to original cost
-Arsenal art updated
-Weapons Depot added using Arsenal's old art
-Arsenal and Military Base's defense reduced to unmodded level
-Defense Satellite's defense reduced slightly
-Reduced maint costs of all defense buildings to the lower tier of their era

Hotfix Update:
-Arsenal's maint is only 2g and Military Base and Defense Satellite's is only 3g to match the buildings of their tiers

Bug Fixes:
-Military Base's help text is updated instead of Military Academy
-Text containing erroneous '' is corrected

Update:
-Satellite tech icon restored to default
-Defense Satellite has new unique icon

Bug Fixes:
-Arsenal and Military Base now provide correct defense rather than 1/10 of it...
-Defense Satellites now actually requires a Military Base

-Walls of Babylon's cost increased to match other buildings of its tier
-Arsenal & Defense Satellites' costs reduced to match other buildings of their tiers
-Arsenal, Military Base, & Defense Satellites' ranged attack bonus slightly increased
-Fixed and updated Defense Satellites' pedia text
-Added a National Wonder for Defense Satellites in every city