Badge updates & License blurb cleanup

[unixorn]

• Update badges in readme
• Update license blurb in the code

[github-actions]

MegaLinter status: ✅ SUCCESS

Descriptor	Linter	Files	Fixed	Errors	Elapsed time
✅ COPYPASTE	jscpd	yes		no	1.03s
✅ CREDENTIALS	secretlint	yes		no	0.78s
✅ GIT	git_diff	yes		no	0.0s
✅ MARKDOWN	markdownlint	1		0	0.32s
✅ MARKDOWN	markdown-table-formatter	1		0	0.41s
✅ PYTHON	black	2		0	0.35s
✅ PYTHON	flake8	2		0	0.3s
✅ PYTHON	isort	2		0	0.13s
✅ PYTHON	mypy	2		0	3.35s
✅ PYTHON	pylint	2		0	1.8s
✅ SPELL	misspell	4		0	0.05s

See errors details in artifact MegaLinter reports on CI Job page
Set VALIDATE_ALL_CODEBASE: true in mega-linter.yml to validate all sources, not only the diff