Distribute `ltitop` in PyPI

[hidmic]

Rationale

Distributing ltitop as a regular Python package is key to ease of use.

Requires #12 and #13.

Definition of Done

• Prepare project for proper packaging
  • Populate setup.cfg
  • Clean up setup.py
  • Add pyproject.toml
• Add project changelog.
  • Use gitchangelog to generate it
• Use PyPI to publish