Add fizzy-app-102 as a replica

The setup here is a bit rough while we settle some of the details, but
the gist of it is:

- Define accessories to run the primary/replica processes
- Add a web-replica role, which is similar to web but has the
  replication-side accessory
- Load the beamer extension on the app's primary tenanted database

Note that we aren't sending any traffic into the replica yet, but it
would be functional to do so. This stage is mainly about testing the
database replication.

config/deploy.yml

@@ -1,10 +1,42 @@
 service: fizzy
 image: basecamp/fizzy
 
+
+x-basecamp-registry: &basecamp-registry
+  username: bcbot
+  password:
+    - BASECAMP_REGISTRY_PASSWORD
+
+x-beamer-accessory: &beamer-accessory
+  image: basecamp/beamer
+  registry:
+    <<: *basecamp-registry
+  options:
+    user: 1000 # Match the UID of the Rails app, for volume permissions
+  volumes:
+    - fizzy:/storage
+
+
 servers:
   jobs:
     cmd: bin/jobs
 
+accessories:
+  beamer-primary:
+    <<: *beamer-accessory
+    service: beamer-primary
+    cmd: beamer primary --debug --remove-after=1h --dir=/storage
+    port: 5000:80
+    roles:
+      - web
+
+  beamer-replica:
+    <<: *beamer-accessory
+    service: beamer-replica
+    cmd: beamer replica --debug --primary=http://fizzy-app-101:5000/ --dir=/storage
+    roles:
+      - web-replica
+
 volumes:
   - fizzy:/rails/storage
 
@@ -12,9 +44,7 @@ proxy:
   ssl: true
 
 registry:
-  username: bcbot
-  password:
-    - BASECAMP_REGISTRY_PASSWORD
+  <<: *basecamp-registry
 
 builder:
   arch: amd64