Refactor HTTP auth modules

[alessfg]

Proposed changes

Refactor the auth HTTP config template into its own separate file, as well as add support for auth_jwt directives. All variables have changed (check defaults/main/template.yml for examples):
* All the various auth variables now live within their respective auth dictionaries.
* auth configs are now supported within the http, server, and location contexts.

Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING document
• I have added Molecule tests that prove my fix is effective or that my feature works
• I have checked that any relevant Molecule tests pass after adding my changes
• I have updated any relevant documentation (defaults/main/*.yml, README.md and CHANGELOG.md)