Add UIViewController to a scroll view

    scrollView.addSubview(tutorialStep.view)

    addChildViewController(tutorialStep)
    tutorialStep.didMoveToParentViewController(self)

Visual alignment for the views

    let views = ["view": view, "page1": page1.view, "page2": page2.view, "page3": page3.view, "page4": page4.view, "page5": page5.view]

    let verticalConstraints =
      NSLayoutConstraint.constraintsWithVisualFormat(
        "V:|[page1(==view)]|", options: nil, metrics: nil, views: views)
    NSLayoutConstraint.activateConstraints(verticalConstraints)

    let horizontalConstraints =
      NSLayoutConstraint.constraintsWithVisualFormat(
        "H:|[page1(==view)][page2(==view)][page3(==view)][page4(==view)][page5(==view)]|", options: .AlignAllTop | .AlignAllBottom, metrics: nil, views: views)
    NSLayoutConstraint.activateConstraints(horizontalConstraints)