Make volume_quotas_client  use **kwargs

As we discussed on
http://lists.openstack.org/pipermail/openstack-dev/2015-July/068864.html
All http POST/PUT methods need to contain **kwargs as their arguments.
This patch makes aggregates_client use **kwargs.

Partially implements blueprint consistent-service-method-names

Change-Id: I58334c3dd6b740129a2d80d2a6dfa61b4548ae08
diff --git a/tempest/services/volume/base/admin/base_volume_quotas_client.py b/tempest/services/volume/base/admin/base_volume_quotas_client.py
index d7909ff..ad8ba03 100644
--- a/tempest/services/volume/base/admin/base_volume_quotas_client.py
+++ b/tempest/services/volume/base/admin/base_volume_quotas_client.py
@@ -50,21 +50,14 @@
         body = self.show_quota_set(tenant_id, params={'usage': True})
         return body
 
-    def update_quota_set(self, tenant_id, gigabytes=None, volumes=None,
-                         snapshots=None):
-        post_body = {}
+    def update_quota_set(self, tenant_id, **kwargs):
+        """Updates quota set
 
-        if gigabytes is not None:
-            post_body['gigabytes'] = gigabytes
-
-        if volumes is not None:
-            post_body['volumes'] = volumes
-
-        if snapshots is not None:
-            post_body['snapshots'] = snapshots
-
-        post_body = jsonutils.dumps({'quota_set': post_body})
-        resp, body = self.put('os-quota-sets/%s' % tenant_id, post_body)
+        Available params: see http://developer.openstack.org/
+                              api-ref-blockstorage-v2.html#updateQuotas-v2
+        """
+        put_body = jsonutils.dumps({'quota_set': kwargs})
+        resp, body = self.put('os-quota-sets/%s' % tenant_id, put_body)
         self.expected_success(200, resp.status)
         body = jsonutils.loads(body)
         return service_client.ResponseBody(resp, body)