[ENH][WIP] Add positionnal arguments

[arnaudbore]

Quick description

Positional arguments become mandatory

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Type of change

Check the relevant options.

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• This change requires a documentation update

Provide data, screenshots, command line to test (if relevant)

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Checklist

• My code follows the style guidelines of this project (run autopep8)
• I added relevant citations to scripts, modules and functions docstrings and descriptions
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I moved all functions from the script file (except the argparser and main) to scilpy modules
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes

[pep8speaks]

Hello @arnaudbore, Thank you for submitting the Pull Request !

• In the file scilpy/io/deprecator.py:

Line 69:80: E501 line too long (89 > 79 characters)

[codecov]

Codecov Report

Attention: Patch coverage is 0% with 1 line in your changes missing coverage. Please review.

Project coverage is 69.54%. Comparing base (0ac4461) to head (b29e9f3).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1118      +/-   ##
==========================================
- Coverage   69.56%   69.54%   -0.03%     
==========================================
  Files         448      448              
  Lines       24078    24077       -1     
  Branches     3290     3290              
==========================================
- Hits        16751    16745       -6     
- Misses       5934     5939       +5     
  Partials     1393     1393              

Components	Coverage Δ
Scripts	70.25% <ø> (ø)
Library	68.60% <0.00%> (-0.06%)	⬇️