Edited text, buttons now indicate selected floor, added clear reservation button

The text itself is different. There's still some styling to do, but I would prefer to do it at a meeting so I can get everyone's opinion on the spot.

The button for the current floor now becomes a different color and disabled. There's a minor bug that makes a small part of most of the buttons not change color. I don't know what the problem is.

I figure that the functionality of the clear reservation button can be added to the click handler.