Delegate for Programmatically Scroll + Lock\Unlock a Page

Hello Pin,

My name is Irad Ratmansky and I was using the PWParallaxScrollView as part of my intro for the app.
I had the need to lock the screen when I had an animation before allowing the user to continue with the intro. The animation started after scrolling programatically to the right page, so I had to get it thru UIScrollView delegate

So I introduced another delegate function and an "enabler" property that locks\unlocks the screen.
I've also expanded the example you had to demonstrate how the new lock\unlock functionality works 

Hope you'll find it useful,
   Irad Ratmansky.