docs: refactor sections, consolidate examples (#1164)

docs/configuration/examples/docker/autocert.docker-compose.yml

@@ -1,18 +0,0 @@
-version: "3"
-services:
-  pomerium:
-    image: pomerium/pomerium:latest
-    environment:
-      # Generate new secret keys. e.g. `head -c32 /dev/urandom | base64`
-      - COOKIE_SECRET=V2JBZk0zWGtsL29UcFUvWjVDWWQ2UHExNXJ0b2VhcDI=
-    volumes:
-      # Use a volume to store ACME certificates
-      - pomerium:/data:rw
-    ports:
-      - 443:443
-
-  # https://httpbin.corp.beyondperimeter.com --> Pomerium --> http://httpbin
-  httpbin:
-    image: kennethreitz/httpbin:latest
-    expose:
-      - 80