Ratio transpose and Ratio interval

[walterbender]

Fixes #3918

By using processPitch for all pitch types, the transformations are applied the same no matter how the pitch is specified.

One caveat: the Scalar and Semitone Step blocks step from the last pitch played; when used inside of any of the transpose blocks, they will step from the previously transposed note, which may produce unexpected results. (This is not a regression, rather it is just more evident.)