Added a 200m lenght race in addition to the default 100m.

I will be adding an option to disable boost, so races can be 100% random (fair for people with delay, giveaways, etc), as well as separate records for each track length.

Tank skin has been removed from the store, but if you bought on older versions you still can wear it. Also, the game will run smoother, especially on 50+ players races!