Add categories to sounds

[AvgZing]

Sounds are currently all "neutral" category; consider changing.

[AvgZing]

This means that all custom sounds can be controlled with 1 volume slider. This is great for being able to disable custom audio, particularly since they're typically played as an @A without range. If playing TCG, this means that you only need to disable the Sounds slider. It's a great life simplifier, even if it's kind of odd to not have this flexibility.
Issue closed and marked as wontfix for now, but will be kept around for a potential future config option.