Optimize Resampler when ratio is 1

[MarkKremer]

Instead of resampling the data, Resampler could pass on the samples as-is when the resample ratio is exactly 1. This could happen, for instance, when the Doppler node measures a constant distance between the audio source and the observer (the audio waves are neither compressed nor stretched).

Still, the buffers must be filled the correct way when doing this in case the ratio becomes non-zero and the previous samples are needed for resampling.