BUG/MINOR: avoid panic in runtime Reload if output is empty

Author: hdurand0710

runtime/runtime_client.go

@@ -186,7 +186,9 @@ func (c *client) Reload() (string, error) {
 	parts := strings.SplitN(output, "\n--\n", 2)
 	if len(parts) == 1 {
 		// No startup logs. This happens when HAProxy is compiled without USE_SHM_OPEN.
-		status = output[:len(output)-1]
+		if len(output) > 0 {
+			status = output[:len(output)-1]
+		}
 	} else {
 		status, logs = parts[0], parts[1]
 	}