Do not allocate memory during WaveNet processing #49
Description
Currently, the WaveNet model processing code re-sizes vectors and matrices based on the audio buffer size during processing. This is non-ideal for real-time operation. Instead, all sizing operations should be done out-of-band of the processing loop.
In most cases, the current behavior should not cause significant problems. If there is a fixed audio buffer size the resize operations should only happen once. A fixed buffer size is not guaranteed, however - DAWs will sometimes vary the block size.