Feature/filestorage securityservices delete (#133)

* sfs: Add support for security services Delete

* sfs: Add acceptance tests for security service Delete
diff --git a/openstack/sharedfilesystems/v2/securityservices/results.go b/openstack/sharedfilesystems/v2/securityservices/results.go
index e34692d..746b2b3 100644
--- a/openstack/sharedfilesystems/v2/securityservices/results.go
+++ b/openstack/sharedfilesystems/v2/securityservices/results.go
@@ -50,3 +50,8 @@
 type CreateResult struct {
 	commonResult
 }
+
+// DeleteResult contains the response body and error from a Delete request.
+type DeleteResult struct {
+	gophercloud.ErrResult
+}