diff data/fft/FFTapi.cpp @ 300:5877d68815c7

* Change WaveFileModel API from getValues(start,end) to getData(start,count).
  It's much less error-prone to pass in frame counts instead of start/end
  locations.  Should have done this ages ago.  This closes #1794563.
* Add option to apply a transform to only the selection region, instead of
  the whole audio.
* (to make the above work properly) Add start frame offset to wave models