Change photoelectron/count calibration to use smoothed data - raw data as
the noise && set up for long scan for a wide range of ODs.
Using masked numpy arrays to select region of interest and background data

Also, added a vectorized numpy function to change nans and infinities to
zeros, and added some extra comments
Cleaned up to take away antiquated isat dependence of the od
Modified file importing to save to numpy files

And used this to generate files of raw data from s-wave scattering
Created a function for interpolating simulated OD at 40us

as a function of initial OD and probe intensity
added a few comments
Made another function for finding the closest simulated point rather than
interpolating - should be faster, but less acurate