Clear background when navigated away from a row
Minor coding style clean up
Remove unused import
Fix coding style issue
Implement BrowserTransitionListener

Overwrite BrowserTransitionListener onHeadersTransitionStop
so the background image is reset when the transition stops.
This a better approach as it handles all the possible way of
scrolling through the list and will act according to the proper state
Merge pull request #22 from eyedol/master

Clear Selected Row's Background When User Navigates away, Fixes #18