Support L2GW plugin/agent

L2 Gateway (L2GW) is an API framework that offers bridging 2+
networks together to make them look as a single broadcast domain.
A typical use case is bridging the virtual with the physical networks.

Related-Prod: PROD-17614
Change-Id: I4101b94202f87da6f5ecdea75d38dde17f08ca99
diff --git a/tests/pillar/gateway_legacy_l2gw.sls b/tests/pillar/gateway_legacy_l2gw.sls
new file mode 100644
index 0000000..d3cd4a8
--- /dev/null
+++ b/tests/pillar/gateway_legacy_l2gw.sls
@@ -0,0 +1,37 @@
+neutron:
+  gateway:
+    agent_mode: legacy
+    backend:
+      engine: ml2
+      tenant_network_types: "flat,vxlan"
+      mechanism:
+        ovs:
+          driver: openvswitch
+    dvr: false
+    enabled: true
+    external_access: True
+    local_ip: 10.1.0.110
+    message_queue:
+      engine: rabbitmq
+      host: 127.0.0.1
+      password: unsegreto
+      port: 5672
+      user: openstack
+      virtual_host: /openstack
+    metadata:
+      host: 127.0.0.1
+      password: password
+      workers: 2
+    version: pike
+    l2gw:
+      enabled: true
+      ovsdb_hosts:
+        ovsdbx: 10.164.5.33:6632
+linux:
+  system:
+    enabled: true
+    repo:
+      mirantis_openstack_pike:
+        source: "deb http://mirror.fuel-infra.org/mcp-repos/pike/xenial pike main"
+        architectures: amd64
+        key_url: "http://mirror.fuel-infra.org/mcp-repos/pike/xenial/archive-mcppike.key"