Simple non-async WavReader

[TobyKLight]

This is a request for a simple WavReader that does not load Async.

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It's related to the same problem as this issue:
#18

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The existing WavReader does load Async but it doesn't tell you when it's finished.
So you can't know it's safe to do things downstream like init the buffer or play.

The purpose of a simple non-async WavReader would be to that you can safely put it in your own Async or Reactive context knowing it will block that context until it completes the read.
Then you can keep it in a reactive stream for further processing. (Which may not necessarily be playing the audio, maybe you want to do some other data processing like peak analysis)

The existing AudioPlayer already covers the simple usecase of playing audio.
I think WavReader & buffer system should enable advanced use like reactive.