Cubeviz parser to load all sorts of s3d cubes

[pllim]

See javerbukh#9

Description

This pull request is to address s3d load failures reported by @havok2063 .

This builds on what work @javerbukh started in #547 .

Good news: I got all the files to load.
Bad news: This is very hacky and broke two plugins.

🐱 🐱

Checklist for package maintainer(s)

This checklist is meant to remind the package maintainer(s) who will review this pull request of some common things to look for. This list is not exhaustive.

• Are two approvals required? Branch protection rule does not check for the second approval. If a second approval is not necessary, please apply the trivial label.
• Do the proposed changes actually accomplish desired goals? Also manually run the affected example notebooks, if necessary.
• Do the proposed changes follow the STScI Style Guides?
• Are tests added/updated as required? If so, do they follow the STScI Style Guides?
• Are docs added/updated as required? If so, do they follow the STScI Style Guides?
• Did the CI pass? If not, are the failures related?
• Is a change log needed? If yes, is it added to CHANGES.rst?
• Is a milestone set? Milestone is only currently required for PRs related to Imviz MVP.
• After merge, any internal documentations need updating (e.g., JIRA, Innerspace)?

[pllim]

I decided to bypass Spectrum1D parsing because of two problems:

1. Spec1D read is slow compared to astropy.io fits.open astropy/specutils#688 (this will be fixed once Speed up jwst s3d loader astropy/specutils#874 is merged)
2. Even if I wait patiently for it to load, Glue tries to swap something in the data translation phase (Spectrum1D -> Data) and fails.

This is what I tried (something like that):

sp = Spectrum1D.read(file_obj, format='JWST s3d') 
app.add_data(sp, data_label)

Because I did not pass in Spectrum1D, but rather native Glue object, line list and unit conversion plugins break because they make certain assumption of the data types.

[pllim]

p.s. Ginga can load the cubes fine and without lag. It does not use specutils, so it is able to take advantage of FITS memory mapping.

[codecov]

Codecov Report

Merging #911 (8f33857) into main (86fce7b) will decrease coverage by 0.46%.
The diff coverage is 36.06%.

@@            Coverage Diff             @@
##             main     #911      +/-   ##
==========================================
- Coverage   68.38%   67.92%   -0.47%     
==========================================
  Files          66       66              
  Lines        4799     4823      +24     
==========================================
- Hits         3282     3276       -6     
- Misses       1517     1547      +30     

Impacted Files	Coverage Δ
...z/configs/default/plugins/line_lists/line_lists.py	39.90% <0.00%> (ø)
jdaviz/configs/cubeviz/plugins/parsers.py	57.57% <35.71%> (-24.48%)	⬇️
...specviz/plugins/unit_conversion/unit_conversion.py	72.84% <50.00%> (-0.81%)	⬇️

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[pllim]

I think it is clearer if we look at javerbukh#9