Unpin redis version (we can trust apt to do the right thing)

playbooks/roles/alton/meta/main.yml

@@ -22,6 +22,5 @@
 dependencies:
   - common
   - supervisor
-  - role: redis
-    redis_debian_pkgs:
-      - "redis-server"
+  - redis
+

playbooks/roles/redis/defaults/main.yml

@@ -29,6 +29,6 @@ redis_group: redis
 #
 
 redis_debian_pkgs:
-  - "redis-server=2:2.8.11-1chl1~precise1"
+  - "redis-server"
 
 redis_redhat_pkgs: []