Move methods related to metering_label

The moved methods are used at test_metering_extensions only, so the
base module is not a good place to keep such methods. This patch moves
them into test_metering_extensions for keeping the base method simple.

Change-Id: I84c36cc3597b53953b4fb9fc7c42932682d44795
diff --git a/tempest/api/network/admin/test_metering_extensions.py b/tempest/api/network/admin/test_metering_extensions.py
index 18dccc3..3f94868 100644
--- a/tempest/api/network/admin/test_metering_extensions.py
+++ b/tempest/api/network/admin/test_metering_extensions.py
@@ -45,6 +45,28 @@
             remote_ip_prefix, direction,
             metering_label_id=cls.metering_label['id'])
 
+    @classmethod
+    def create_metering_label(cls, name, description):
+        """Wrapper utility that returns a test metering label."""
+        body = cls.admin_metering_labels_client.create_metering_label(
+            description=description,
+            name=name)
+        metering_label = body['metering_label']
+        cls.metering_labels.append(metering_label)
+        return metering_label
+
+    @classmethod
+    def create_metering_label_rule(cls, remote_ip_prefix, direction,
+                                   metering_label_id):
+        """Wrapper utility that returns a test metering label rule."""
+        client = cls.admin_metering_label_rules_client
+        body = client.create_metering_label_rule(
+            remote_ip_prefix=remote_ip_prefix, direction=direction,
+            metering_label_id=metering_label_id)
+        metering_label_rule = body['metering_label_rule']
+        cls.metering_label_rules.append(metering_label_rule)
+        return metering_label_rule
+
     def _delete_metering_label(self, metering_label_id):
         # Deletes a label and verifies if it is deleted or not
         self.admin_metering_labels_client.delete_metering_label(
diff --git a/tempest/api/network/base.py b/tempest/api/network/base.py
index 359a444..8775495 100644
--- a/tempest/api/network/base.py
+++ b/tempest/api/network/base.py
@@ -269,25 +269,3 @@
         cls.admin_metering_labels_client = cls.os_admin.metering_labels_client
         cls.admin_metering_label_rules_client = (
             cls.os_admin.metering_label_rules_client)
-
-    @classmethod
-    def create_metering_label(cls, name, description):
-        """Wrapper utility that returns a test metering label."""
-        body = cls.admin_metering_labels_client.create_metering_label(
-            description=description,
-            name=name)
-        metering_label = body['metering_label']
-        cls.metering_labels.append(metering_label)
-        return metering_label
-
-    @classmethod
-    def create_metering_label_rule(cls, remote_ip_prefix, direction,
-                                   metering_label_id):
-        """Wrapper utility that returns a test metering label rule."""
-        client = cls.admin_metering_label_rules_client
-        body = client.create_metering_label_rule(
-            remote_ip_prefix=remote_ip_prefix, direction=direction,
-            metering_label_id=metering_label_id)
-        metering_label_rule = body['metering_label_rule']
-        cls.metering_label_rules.append(metering_label_rule)
-        return metering_label_rule