Updated oldScroll value so that top most waypoints would be active on page load

Updated oldScroll value so that top most waypoints would be active on page load.
I'm not certain if there are any risks in setting this initialization value to -1.  I will be looking at the rest of the code tomorrow so I'll keep my eye out for issues as I go.  I had been hacking around this init thing, but I decided to just fork and see what I could see.