HIRES wavelengths

[profxj]

Testing for pypeit/PypeIt#1628

[profxj]

And development files.

Make me put in a redo_slits test on a multislit spectrograph
as a vet test, before merging.

[profxj]

this is a reminder to myself to remove the setups list
in test_setups.py before merging

[kbwestfall]

I'm "requesting changes" so that we can discuss the following three points:

• I'm a little worried about how you're importing stuff from local files by adding the local directory to the path. I give you a way around this that feels cleaner, but let me know what you think.
• I'd prefer that we not overwrite the original slits file in your test.
• I'm wondering if there's a better/cleaner directory structure for the pypeit files that are used for the reduce tests vs. those that are needed for more bespoke vet/unit tests.

[kbwestfall]

Looks great!