chore: Mild reorganization of project files for better dev experience, tidiness

[sehwol]

Self assigned, if the repo owner gives permission.

I'd like to move wiktionaryparser.py and the utils.py into a new wiktionaryparser folder, making the project structure conform to the structures of other Python repositories.

I'll make sure to add a CONTRIBUTING.md with the shell script contributors can copy paste to get their dev env setup (venv, pip install -e .).

I'll also make sure to add the classes in utils.py to __all__ so the API doesn't change.

The aim's just to:

• Make the repo tidier.
• Make Intellisense work again since, for some reason, the current project structure is preventing it from doing autocompletion.
• Pave the way for absolute imports.

[Suyash]

This makes sense. I'd not given much thought to project structure initially. Feel free to submit a PR for this!