Adding DeleteResult for v3.tokens.Delete
diff --git a/openstack/identity/v3/tokens/requests.go b/openstack/identity/v3/tokens/requests.go
index 351d7d6..5ca1031 100644
--- a/openstack/identity/v3/tokens/requests.go
+++ b/openstack/identity/v3/tokens/requests.go
@@ -276,10 +276,11 @@
 }
 
 // Revoke immediately makes specified token invalid.
-func Revoke(c *gophercloud.ServiceClient, token string) error {
-	_, err := perigee.Request("DELETE", tokenURL(c), perigee.Options{
+func Revoke(c *gophercloud.ServiceClient, token string) RevokeResult {
+	var res RevokeResult
+	_, res.Err = perigee.Request("DELETE", tokenURL(c), perigee.Options{
 		MoreHeaders: subjectTokenHeaders(c, token),
 		OkCodes:     []int{204},
 	})
-	return err
+	return res
 }