Earth3 remake 2016-10-05

This is an Earth3 remake.

Credit for idea goes to jkp1187.

Thanks to LDiCesare's Tectonics script, GRM7584's original Earth2 and invaluable help by CivFanatics members in helping me complete this task.

This script basically generates Earth2 with several caveats:
- Minimum of 1 civ per continent.
- Minimum starting landmass of 12 tiles

Tested this several times now and it runs perfectly.