The major U.S. index futures are currently pointing to a roughly flat open on Tuesday, with stocks likely to show a lack of direction after ending the previous session mostly higher.Traders may be reluctant to make significant moves as they keep an eye on developments on Washington, where lawmakers once again failed to pass a temporary spending bill last night.While traders have largely shrugged off the government shutdown in recent sessions, the subsequent lack of major U.S. economic data may keep some in ...