Make velocities realistic

[andycate]

We should make it so that when you animate the path, the velocity of the animation is relatively close to what the actual robot will do. We may even want to have an Estimated Drive Time counter. There should be a little settings window where you can adjust different robot parameters so that the animation is accurate.

[andycate]

FYI, this is a bit more involved of an issue than some others, so if you are less experienced, try tackling one of the other issues first. Otherwise, go for it!