Added Page Up and Page Down to keyboard commands, to complete issue #41
Added Home and End buttons to keyboard commands
Added _preventDefaultstopPropagation, refactored code to use it.
Merge pull request #54 from MartijnRas/master

Added Page Up and Page Down to keyboard commands, to complete issue #41

Thanks to @MartijnRas
One day, I would have to replace those event propagation/prevention lines by something better! Thanks for doing it proactively!
Also, nice new feature, using home and end as a "go to" to the first and last slides!