Transport Fever 2 - Map Generators Plus

Adds a new set of map generators for each default type which allow setting the values higher.
Also adds some extra sliders for the temperate and desert generators.

Higher than normal values may produce weird results.
Note that adding to much hilliness may stop towns/industries from generating. I have not found a way to allow them to spawn in rougher areas yet.
The slider ranges are pretty much arbritraty at the moment.

As a map generator mod, this mod is not enabled in the mod menu. Instead, new the generators are added as options on the map generator screen.

Authors: oln