Improve networks

Create a single external network called "external".
Create container-specific networks.
Only a few containers need access to these.
So far: openldap, postgres.

roles/nginx/tasks/main.yml

@@ -14,11 +14,11 @@
 - name: generate self-signed certs
   import_tasks: self-signed.yml
   when: self_signed
-- name: create nginx bridge network
+- name: create external bridge network
   docker_network:
-    name: nginx-internal
+    name: external
     attachable: true
-    internal: true
+    internal: false
     state: present
 - name: copy nginx.conf
   template:
@@ -37,8 +37,7 @@
     name: 'nginx'
     image: nginx
     networks:
-      - name: bridge
-      - name: nginx-internal
+      - name: external
     volumes:
       - "{{ data_folder }}/nginx/conf.d:/etc/nginx/conf.d"
       - "{{ data_folder }}/nginx/nginx.conf:/etc/nginx/nginx.conf"