- Automatic Flux Scaling

- new function scalespectra() automatically scales each spectrum to one
perhaps-user-chosen spectrum (generally the one with the median
gr-angle) so that the flux values of all spectra are similar at
overlapping wavelengths. This scaling (second-order) function is applied
to entire spectra rather than just the overlapping parts.
- In maskspectra(), the pipeline now automatically goes back and sets
the chip gap regions (+/- some pixels) to 1. This accounts for any
potentially misidentified "good" pixels within the chip gaps.
- The ~invariant pixel numbers of the first chip gap (with a generous
surrounding region) are 1035-1105. For the second chip gap, they are
2115-2180.
- The change to maskspectra() now produces a rather smooth final
spectrum with odcombine.
- What remains to be done is to correct for telluric absorption lines
during/before the flux calibration step.