Added new expression to create a volume category

[a] [new] [voice chat] volume category with id %string% named %string% [with description %-string%]

• Removed the static sound packets from the on microphone event because Skript is too slow, and causes Voice chat to lose packets. I've experimented with multiple solutions, and it's always too slow. Only thing I could think of was to make a custom structure, which I may come back to at some point.