* removed all cases of getting a sound handle and checking it later.
* In particular, refactor the cases where the handle is stored in a static local variable. These are fundamentally unsafe because nothing maintains these local variables.
* finished rewriting the PlaySound function. Let's hope this is what was intended, the entire coding here was not particularly good, mixing high and low level sound handling all on the same level.
* call the update routine each tic and not merely every 4th or 8th one, this kind of granularity was ok in 1997 but not with a modern sound engine.
* removed old sound loading code, which was the last bit to use cacheAllocateBlock which is also gone now.
* cleanup of player sound code. All game side tracking of the sound resources has been removed.
does not compile yet.
* reverb/echo is not yet implemented, so there's two stub functions for now.
* RTS needs to be done differently, because the sound engine cannot play raw buffers without any control data.
