/sound.pitch not implemented

[ZeWaka]

Can be used to shift the pitch of a sound up or down. This works similarly to frequency except that it doesn't impact playback speed.
The value of this var should be a multiple relative to 1, so for instance to go up a full octave, the value would be 2; to go down an octave, use 0.5.

Potential way to improve upon BYOND's impl:

The filter that handles pitch shifting only goes from 0.5 to 2. The player will stack up to three filters if it has to, so the range is really from 0.125 to 8. You will however hear much poorer quality at more extreme values.

https://www.byond.com/docs/ref/#/sound/var/pitch

[amylizzle]

Closed in favour of #2194