fix: support UUIDs as per RFC spec (#50)

[aikrom]

Proposed changes

Added support uppercase/lowercase UUIDs as per RFC spec.

Types of changes

• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)

Checklist

• I have read the CONTRIBUTING doc
• Lint and unit tests pass locally with my changes
• I have added tests that prove my fix is effective or that my feature works.
• I have added necessary documentation (if appropriate)

[thetutlage]

Thanks! Finally, let's have a test that validates case insensitive uuid and casts it to lower

[thetutlage]

Merging, as I am already working on a release. I will add the required tests myself