Editor: Checkpoint list

[cshaa]

While editing a track, it's hard to find all the checkpoints (since some of them may be eg. underground). It would be great (and not so hard, I think) to add a "Checkpoints" list. Clicking on items in it would move the camera to show the checkpoint. Right-clicking would show a delete option and move up/down options (using html5 contextmenu attribute).

It's a great game and I look forward to next versions.