Update gumby.inview.js

Inview is not working for me on pagerefresh in FF 28.0
The .onscreen class gets added only after scrolling or resizing the window.
With an added $(window).load() function triggering the scroll event the problem is solved.
Merge pull request #1 from dycedesign/patch-1

Inview not working on page refresh in Firefox (no .onscreen class gets added)