End_Source For Music

[lowypan]

There is already a start_source
but some original game tracks like "Black Light" have some type of Fade Out

so, we need that.

[Luffyyy]

Recommend it here instead https://github.com/simon-wh/PAYDAY-2-BeardLib since this is just the editor and has nothing to do with loading content.

[lowypan]

ups