[enhancement] map properties support

[tlitookilakin]

A great way to make this easier on map makers and more compatible with various farm types would be to add support for built-in map properties.

Essentially, if a map had the property "farmtypemanagerdata", which would contain a JSON string, the mod would read that when the game loads, and interpret the JSON in it the same way it currently does the configs, but using the name of the map it comes from instead of the "mapname" property.