SciDAVis - Improvements SVN-temp

Savitzky-Golay smoothing.
- Reimplemented Savitzky-Golay smoothing from scratch, based on information
found at http://www.statistics4u.info/fundstat_eng/cc_filter_savgol_math.html
and routines provided by the GSL. The new implementation features improved
handling of values near the endpoints of the input data; namely, instead of
effectively zero-padding the data, the smoothing polynomial obtained from a
fixed window is used to compute the output values in question.