mention drag and drop in the about page

Now no need to manually transcribe keys when drag and drop will do it for you.

I changed the example. Since it mentioned drag and drop, but wasn't this drag and drop, I thought it would be really confusing. I chose instead the awesome DIY video comparing a daily commute to the Tour de France. I was writing with the 2014 Tour on the TV so I credit that for inspiration. Yorkshire at this very moment.