Add travis for CI purposes
Make sure that grunt-cli is in there for travis
Update README.md

Add travis badge.
Prevents snapping to slide during post-scroll momentum movement
This moves the setting of a scrollLeft value to within the debounced
part of the scroll handler, so snapping isn’t attempted during any form
of scrolling. This issue is visible when “throwing” a particularly long
sidescroller area.
Retains current slide position, if possible, when the browser window is resized.