docs: add docs for compose ports and path routes

[shreddedbacon]

General Checklist

• Affected Issues have been mentioned in the Closing issues section
• Documentation has been written/updated
• PR title is ready for inclusion in changelog

Database Migrations

• If your PR contains a database migation, it MUST be the latest in date order alphabetically

Added documentation describing the lagoon.service.usecomposeports label and how it can be used.

Also added documentation to describe path based routes and how to configure them.

Additionally, tweaked additional volumes to show how they can be used without a -persistent service type. Added a note that new projects should use non -persistent service types with additional volumes. As we should really promote this as the way to do persistent volumes instead of the older -persistent types.

Closing issues

closes #3832

[tobybellwood]

Looks good to me!