Make the location of the model configurable

[Kokujou]

I just noticed when installing that the Application is installed in AppData\Local but the Model itself is in the Users directory. for me personally that's problematic because i don't have much space on my C drive anymore and since the model is quite big (and i assume it will rather go bigger than smaller) one should be able to put it on a bigger hard drive than C.

i think it's quite common sense to only use the C drive being a very fast but as a result also small drive for programs and the operation system while mass data lies on bigger HDDs, so it'd be nice to make the path to the model .bin file configurable somehow.

either that, or at least put it in the same directory as the application is and use a relative path, so one could simply move it from AppData\Local to any other location.