#758 Base pitch range vs tone range adjustments done with Praat analysis.

Additional improvements to Cherokee. Adjusted the core pitch range to fix an issue with 'g' vs 'd' and increased the pitch range and have the starting and stopping points on the pitch contours much closer to my reference document.

TODO: devoiced vowels TODO: wh/hw, yh/yh TODO: Add Eastern Cherokee variant. (s->sh, dZ->tZ, etc.)