commandhandler race condition

When running Signer or Enforcer-ng in gdb the command handler does not seem to listen to the socket. First argument of select has a count+1 rather than a max+1.

• ret = select(ODS_SE_MAX_HANDLERS+1, &rset, NULL, NULL, NULL);
  + ret = select(cmdhandler->listen_fd+1, &rset, NULL, NULL, NULL);