Adding Umami Analytics Support

[rterakedis]

Adding support for https://umami.is/ analytics.

Pull Request type

Please check the type of change your PR introduces:

• Bug-fix
• Feature (functionality, design, translations, etc.)
• Documentation change
• Project management (tests, CI, GitHub configuration, etc.)
• Other (please describe):

Current state

Issue Number(s): Not related to a current issue.

Proposed changes

Add support for Umami analytics. This change adds code to analytics.html partial (adding the umami script reference), params.toml (for the configuration), and Readme.md for the detail on how to configure.

Screenshots, if applicable

Checklist

• Bug-fixes and new features: I have tested locally with the latest release of Hugo extended. This requirement is a standard.
• Bug-fixes, new features, and doc changes: I have updated the relevant documentation as part of this PR.
• All PRs: I have signed off (using git commit -s ...), or if not possible due to developer environment constraints, will comment below confirming that I am adhering to the Developer Certificate of Origin.

[chipzoller]

Thanks for this! Looks ok to me, requesting review from @onweru.