Re-Introduce Clamping Options

[Daniel Marsh-Patrick]

This was originally coded in, and with the introduction of #72 and #66, we can probably take another look at it.

Issues to get working:

• Make sure min.max are included when sampling resolution is too low to include them in the KDE plot (much like how we extend/interpolate when necessary).
• When the clamp is applied, the border just cuts off. it would be nice to make it converge at the clamp point also.

[Daniel Marsh-Patrick]

#74: Added clamping of violin to min/max values in each category. Resolves #74.

→ <<cset f3cf298e1adc>>