Figure out unmapped indices

[stadust]

Right now there are many unmapped indices (meaning fields called index_XX in the models). It'd be nice to figure out their meaning and properly (de)serialize and name them.

A good place to start would probably to look at things like Cvoltons GDPS or nekit''s gd.py.

Alternatively, one can try to figure out which fields seem to be missing, open GD and wireshark, and try to specifically manipulate said field in-game so see how the requests/responses change.