registry: type too many requests error

Signed-off-by: Antonio Murdaca <runcom@redhat.com>

docs/api/errcode/register.go

@@ -63,6 +63,16 @@ var (
 		Description:    "Returned when a service is not available",
 		HTTPStatusCode: http.StatusServiceUnavailable,
 	})
+
+	// ErrorCodeTooManyRequests is returned if a client attempts too many
+	// times to contact a service endpoint.
+	ErrorCodeTooManyRequests = Register("errcode", ErrorDescriptor{
+		Value:   "TOOMANYREQUESTS",
+		Message: "too many requests",
+		Description: `Returned when a client attempts to contact a
+		service too many times`,
+		HTTPStatusCode: http.StatusTooManyRequests,
+	})
 )
 
 var nextCode = 1000