Add the ability to assign textures to a model randomly

[Jin-Jiyunsun]

Is your feature request related to a problem? Please describe.
Textures on for example trees, can get a bit repetitive when Jagex place the same tree over and over in certain areas.

Describe the solution you'd like
The ability to vary the texture so trees leaves texture with the same model can be lighter, darker or different in some other way.

Describe alternatives you've considered
n/a

Additional context
n/a

[aHooder]

This will ultimately require the ability to upload separate vertex data for the same Model instance drawn in different locations. The issue currently is that the model instance RuneLite instructs us to draw holds info about offsets into vertex buffers on the GPU side, so we would have to either add some indirection or potentially reserve space for more than one model, then upload different variants to predictable offsets relative to the buffer offset stored in the Model instance.