onScroll event plz

[mafar]

Hi,
U have slimscroll event which only triggers when it reaches top or bottom.
However this is not helpful in situations like where i want to mark some data as read , i need event onScrolling which triggers during user scrolling , so i can fetch elements and check if they are inviewport then mark them as read.

[mafar]

I added a pull , plz check
#184