doc: Add badges for code features (#55)

README.md

@@ -1,4 +1,13 @@
- [![code-testing](https://github.com/titom73/eos-downloader/actions/workflows/pr-management.yml/badge.svg?event=push)](https://github.com/titom73/eos-downloader/actions/workflows/pr-management.yml) ![PyPI - Python Version](https://img.shields.io/pypi/pyversions/eos-downloader) ![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/titom73/arista-downloader) ![PyPI - Downloads/month](https://img.shields.io/pypi/dm/eos-downloader)
+[![tests](https://github.com/titom73/eos-downloader/actions/workflows/pr-management.yml/badge.svg?event=push)](https://github.com/titom73/eos-downloader/actions/workflows/pr-management.yml)
+![PyPI - Python Version](https://img.shields.io/pypi/pyversions/eos-downloader)
+[![Code style: black](https://img.shields.io/badge/code%20style-black-000000.svg)](https://github.com/psf/black)
+![Checked with mypy](http://www.mypy-lang.org/static/mypy_badge.svg)
+![GitHub release](https://img.shields.io/github/v/release/titom73/arista-downloader)
+![PyPI - Downloads/month](https://img.shields.io/pypi/dm/eos-downloader)
+
+<!--
+[![pre-commit](https://img.shields.io/badge/pre--commit-enabled-brightgreen?logo=pre-commit&logoColor=white)](https://github.com/pre-commit/pre-commit)
+!-->
 
 # Arista Software Downloader