add elasticsearch and etcd to hosts

The swift runtime overrides group_vars/all to add back some
no longer supported Swift runtimes, so for now just replicate
the host file updates from the core repo.  We need to revisit this...
diff --git a/ansible/environments/local/hosts b/ansible/environments/local/hosts
index 7ee31f2..085f5d2 100644
--- a/ansible/environments/local/hosts
+++ b/ansible/environments/local/hosts
@@ -39,8 +39,14 @@
 [db]
 172.17.0.1          ansible_host=172.17.0.1 ansible_connection=local
 
+[elasticsearch:children]
+db
+
 [redis]
 172.17.0.1          ansible_host=172.17.0.1 ansible_connection=local
 
 [apigateway]
 172.17.0.1          ansible_host=172.17.0.1 ansible_connection=local
+
+[etcd]
+etcd0            ansible_host=172.17.0.1 ansible_connection=local