Python: Added basic structure

[ahcorde]

🎉 New feature

This PR is part of this mete ticket #931

Summary

This PR add the basic structure to create Python binding using pybind11

Test it

Compile the code, export the pythonpath and run the example

export PYTHONPATH=$PYTHONPATH:<path to ws>/install/lib/python
python3 examples/python/python_sdformat.py

Checklist

• Signed all commits for DCO
• Added tests
• Added example and/or tutorial
• Updated documentation (as needed)
• Updated migration guide (as needed)
• codecheck passed (See contributing)
• All tests passed (See test coverage)
• While waiting for a review on your PR, please help review another open pull request to support the maintainers

Note to maintainers: Remember to use Squash-Merge and edit the commit message to match the pull request summary while retaining Signed-off-by messages.

[codecov-commenter]

Codecov Report

Merging #932 (2db0690) into main (6e7336c) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #932   +/-   ##
=======================================
  Coverage   88.16%   88.16%           
=======================================
  Files         100      100           
  Lines       14637    14637           
=======================================
  Hits        12905    12905           
  Misses       1732     1732           

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[scpeters]

there is already some code to find python up at lines 60-90; we should unify that code with this

[ahcorde]

05545f8

[azeey]

Should we set the cmake_minimum_required version to 3.12 since main is
targetting focal and later? This will ensure that we're using find_package(Python3) in ign-cmake.