Update for new Visibilities object and some tidy

[samaloney]

• Upate internal code for new vis object
• Update imaging demo to use new vis object feature (slice, meta)
• Small tidy ups

[codecov]

Codecov Report

Attention: Patch coverage is 47.45763% with 31 lines in your changes missing coverage. Please review.

Project coverage is 72.30%. Comparing base (2854ed9) to head (a847cc3).
Report is 8 commits behind head on main.

Files with missing lines	Patch %	Lines
stixpy/calibration/visibility.py	43.58%	22 Missing ⚠️
stixpy/imaging/em.py	55.00%	9 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #124      +/-   ##
==========================================
- Coverage   72.57%   72.30%   -0.28%     
==========================================
  Files          31       31              
  Lines        1856     1892      +36     
==========================================
+ Hits         1347     1368      +21     
- Misses        509      524      +15     

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[paolomassa]

Why is the map created outside of clean? Is it possible to make it inside as for the other methods?

[samaloney]

Currently vis_clean makes a map assuming helioprojective which in this case is not correct.

[samaloney]

Essentially once TCDSolar/xrayvision/issues/56 is done issue is resolved this won't be necessary