SineWave has growing levels of distortion over time because of float round off errors

[mlindner]

This is one of the two issues found in https://github.com/tomaka/rodio/issues/201.

There's random noise that creeps in as the float32 shifts exponent sizes as shown in the image below. The image below is a constant 3000 hz sine wave. In the top part of the image is a waterfall plot showing the growing frequency distortion spread as the float errors increase.