Implement Analysis functions for Smooth
* running average with weight (centered/lagged) - DONE
* percentile filter - DONE
* Savitzky-Golay - DONE
* LOESS/LOWESS/RLOESS/RLOWESS
* Bezier curves (de Casteljau)
* B-spline (de Boor, see GSL)
* ( Fourier low pass filter)ing