Add XML parsing script

[AdrianDAlessandro]

Description

This PR adds the XML parsing script as-is into the repo. The only changes made to it have been to keep pre-commit happy and to wrap the script in an if __name__ == "__main__": block.

Fixes #124

Type of change

• Documentation (non-breaking change that adds or improves the documentation)
• New feature (non-breaking change which adds functionality)
• Optimization (non-breaking, back-end change that speeds up the code)
• Bug fix (non-breaking change which fixes an issue)
• Breaking change (whatever its nature)

Key checklist

• All tests pass (eg. pytest)
• The documentation builds and looks OK (eg. mkdocs)
• Pre-commit hooks run successfully (eg. pre-commit run --all-files)

Further checks

• Code is commented, particularly in hard-to-understand areas
• Tests added or an issue has been opened to tackle that in the future. (Indicate issue here: # (issue))

[alexdewar]

I've made one small suggestion. Other than that, how about a docstring at the top of the file just saying what the file is for and why it is the way it is? Doesn't have to be a long one.

[alexdewar]

I know the plan was to commit this script verbatim for now, but I'm wondering if we could make this script a lot more useful by just allowing the user to pass in paths to one or more XML files as arguments, so people can do:

python -m autocorpus.parse_xml my_file.xml

[AdrianDAlessandro]

I've done this now. Can you merge this if you're happy with it?

[Antoinelfr]

sgtm