Option to write solution files after every major iteration

[joanibal]

Purpose

This is another solver dev/debugging tool.
It makes it easy to print the solution after every major iterations to identify patterns in the converged states and residuals.

Type of change

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (non-backwards-compatible fix or feature)
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no API changes)
• Documentation update
• Maintenance update
• Other (please describe)

Testing

add the option writeSolutionEachIter to a runscript.

Checklist

• I have run flake8 and black to make sure the code adheres to PEP-8 and is consistently formatted
• I have run unit and regression tests which pass locally with my changes
• I have added new tests that prove my fix is effective or that my feature works
• I have added necessary documentation

[codecov]

Codecov Report

Merging #187 (64be139) into master (9bfbeb2) will increase coverage by 0.03%.
The diff coverage is 100.00%.

❗ Current head 64be139 differs from pull request most recent head bbdf017. Consider uploading reports for the commit bbdf017 to get more accurate results

@@            Coverage Diff             @@
##           master     #187      +/-   ##
==========================================
+ Coverage   43.10%   43.14%   +0.03%     
==========================================
  Files          15       15              
  Lines        3519     3521       +2     
==========================================
+ Hits         1517     1519       +2     
  Misses       2002     2002              

Impacted Files	Coverage Δ
adflow/pyADflow.py	67.48% <100.00%> (+0.03%)	⬆️

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[marcomangano]

Just added a couple of general comments, the PR looks good but others should review this

[joanibal]

This is somehow broken at the moment.
Hold off on reviewing.

[joanibal]

This is ready for review again

[anilyil]

Hey, sorry I did not saw this last commit and also slightly modified the docs myself. I agree with @marcomangano that calling it a Major iteration in any way is confusing. Great functionality, plus its useful for making convergence movies too!