Migrate network API tests to resource_* fixtures

Partially-implements bp resource-cleanup

Change-Id: I455c372f7356343f4398f69255c6150c3521b953
diff --git a/tempest/api/network/test_networks.py b/tempest/api/network/test_networks.py
index f3da614..e1eb48d 100644
--- a/tempest/api/network/test_networks.py
+++ b/tempest/api/network/test_networks.py
@@ -59,9 +59,8 @@
     """
 
     @classmethod
-    @test.safe_setup
-    def setUpClass(cls):
-        super(NetworksTestJSON, cls).setUpClass()
+    def resource_setup(cls):
+        super(NetworksTestJSON, cls).resource_setup()
         cls.network = cls.create_network()
         cls.name = cls.network['name']
         cls.subnet = cls.create_subnet(cls.network)
@@ -366,11 +365,11 @@
     _ip_version = 6
 
     @classmethod
-    def setUpClass(cls):
+    def resource_setup(cls):
         if not CONF.network_feature_enabled.ipv6:
             skip_msg = "IPv6 Tests are disabled."
             raise cls.skipException(skip_msg)
-        super(NetworksIpV6TestJSON, cls).setUpClass()
+        super(NetworksIpV6TestJSON, cls).resource_setup()
 
     @test.attr(type='smoke')
     def test_create_delete_subnet_with_gw(self):