FS19 - Category Adder V1.0

- Moves the "AquaTrans", "MKS 8", "MKS 32", and "FST 990" into a new category called "Liquid Transport".
- Moves the "Water Station", "Lime Station" (GS mod), and Placeable Refill Stations (GS mod) into a new category called "Refill Stations".
- Allows mods to create and use a new store category. Same method as using a new brand. (See "Instructions.txt" for more detail)

Authors: ViperGTS96