VIES inspection

[tappoz]

This PR provides:

• Support for VIES inspections to retrieve VAT information about any registered company in the European Union.
• A handy PyPI badge in the README.md file to be able to link the Github repo with the PyPI page for this project.

Unfortunately there must be a silly mistake in the way I implemented the CLI feature, because it throws an error when invoked like:

a38tool vies --country-code IT --vat-number 00934460049

From looking at the code it seems some obvious gotcha that at the moment I am not finding. What's missing?
If this gets sorted, then I would like to document some context around VIES in the README.md if that's fine with you.

Reference:

• https://ec.europa.eu/taxation_customs/vies/vatResponse.html
• https://en.wikipedia.org/wiki/VAT_Information_Exchange_System