All wonder actors look as if they're made out of stone. In game they cost 1000 of each resource. This patch removes the food cost and doubles the stone cost, keeping the resource total unchanged at 4000. Wonders are very much larger than fortresses, therefore it makes sense they cost more stone (still a lot less than the 5000 present in a stone quarry), and food is a resource for units (and technologies); like other structures, it indirectly costs food, because builders cost food to train, and can't work farms when building the structures or quarrying stone.
Also converted the food cost of the `kush_pyramid_small.xml`, the only other structure that costs food, into wood. For comparison, `kush_pyramid.xml` and `kush_pyramid_large.xml` cost stone and metal.