Mavericks installer error message outdated

[ilov...@icloud.com]

Björn,

 if(!(my.target.systemVersion && /* < */ system.compareVersions(my.target.systemVersion.ProductVersion, '10.10') < 0)) {

    my.result.title = 'Failure';

    my.result.message = 'Mac ZFS is only certified to run on Mac OSX Leopard to Mountain Lion.';

    my.result.type = 'Fatal';

    return false;

  }

  return true;

s/Mountain Lion/Mavericks/