Musical sounds to be used with wlogic `playsound`

[SkyeTheFoxyFox]

Adds several musical sounds that fit the style of the existing mindustry music, intended to be used with the world logic playsound instruction to allow map makers and logic developers to make their own music and jingles for their maps/logic.

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[JasonP01]

i feel like you should prefix the file names with logic_ just so its clear the sounds are used by logic. Though they would look funny in the selection dialog, a logic folder in the sounds directory could be used but then you would need to touch the where it crawls for sounds :(