Telluric wavelength solution

[kgullikson88]

Kyle and I worked on this during the UT hack day last week. It runs as another pipeline recipe to be run after reducing the A0V standard stars. What it does is:

• Use the recipe log to find all the A0 stars
• Read in a generic telluric model
• For each A0 star spectrum:
  • Read in spectrum
  • Fit each order separately by shifting the wavelengths until the telluric lines match with the model
  • Fit the entire chip using the pixel numbers and echelle order numbers of each telluric line in the model.
  • Apply the fit to all of the original data
  • Output a file SDCwave.fits, which has the same format as the SDCspec.fits file in outdata/

It also outputs a whole bunch of figures that may or may not be particularly useful in the qa/ directory. I have done some very limited testing and it has worked well, but I can't totally guarantee that it will work.

[kfkaplan]

Closing this pull request since this code was added to the master branch long ago, but see issue https://github.com/igrins/plp/issues/23