Endpoint support

This is to go along with https://github.com/my-koop/service.website/pull/186. I added a couple of example endpoints (although not used here) to show what's possible. These will be moved to https://github.com/my-koop/module.base shortly.
I first tried doing it the way it's done in https://github.com/my-koop/module.base, but it was failing when I wanted to use `metadata.endpoints` in other files, tough luck.