Realistic Resource Yields V. 3.03

Added +1 Food as the base yield for the Camp

Updated the descriptions of the Camp and Plantation

Fixed the issue with Gold yields attaching to all terrains when the Commercial Hub is constructed. They now only go to Resources.

Moved gold yields for sea resources to the Harbor.

Gypsum no longer gets the food yield directly. Now gets a food yield when a Research Lab is built.

Camp now gets +1 food at Rifling and +1 food at Electricity.
Fishing Boats now get +1 food at Steam Power and +1 food at Electricity.
Mine now gets +1 production at Engineering and +1 production at Industrialization.
Pasture now gets +1 food at Feudalism and +1 food at Electricity.
Plantation now gets +1 food at Feudalism and +1 food at Chemistry.
Quarry now gets +1 production at Combustion.

Moved yields around between resources and improvements. The goal is for yields to appear at a more realistic time in history.

Removed base Gold yields. All resources now receive Gold yields when a Commercial Hub is constructed.