Fixed: renamed/condensed page offset arrays for clarity

-Removed references to pageTopOffsets/pageLeftOffsets

-Renamed heightAbovePages/widthLeftOfPages to pageTopOffsets/pageLeftOffsets
Fixed: resolving conflicts
Merge branch 'horiz-scrolling' of https://github.com/ddmal/diva.js into horiz-scrolling

Conflicts:
	source/js/diva.js
Fixed: cross-browser compatibility with transform CSS rule