* Fixed tests checking for mod correctness
* Update G&K jsons to current vanilla versions
* First pass over buildings & beliefs
* First pass over nations
* First pass over eras.json
* Fully updated tech tree
* First pass over units
* Second pass over buildings -- fixed techs
* Fixed last prerequisites and row numbers of tech
* Went through the entire tech tree and moved things to their correct spot
* Fixed tests
* Copied files for Gods & Kings folder
* Added G&K and unified with mods in dropdown
* Split the baseruleset from the mods list in game parameters
* Mod links are checked again when selecting a mod
* The new map editor screen now also uses the base ruleset
* Updated the ruleset change dialog in the map editor; Fixed a crash
* Refactored some code and fixed some bugs
