make_spectra notebook crashes in binder

[jonesmg]

Opening a new issue to track progress on fixes/workarounds for the kernel dying in binder when the make_spectra notebook is run. See also the discussion in #3

[jonesmg]

Today I tried separating all the plotting commands into a function that I then run for each group, in order to attempt to cut off memory leaks or the formation of other excess garbage. This didn't fix the issue of the kernel dying at the same point in every execution. I also commented out all plotting commands (and only left the spectra calculations and updates to the tables). The script still crashed, suggesting it is not only the plotting commands that are causing the issue. Perhaps there is also an issue when the fits files are read in.