"Restart" on success seems odd

[harry-wood]

When I first played this, it seemed weird that after a completing a level I was only given the option to "Restart".

As a quick fix I'd say maybe the "Restart" button should be renamed as "New level" or "Next track" or something, because it just feels a bit too negative to "restart" after succeeding.

But related this... https://github.com/FEDE0D/Planet-Rider/issues/2