move with arrow keys finished prototype
credits: Thanks to google for the anti-collision idea Thanks to https://www.atlist.com/showcase/satelite-map-with-no-labels for real map variable meanings: st: turn speed sx: x speed sy: y speed tpwr: turning power accpwr: acceleration power spd: speed prevx: previous x prevy: previous y prevxx: previous x (game loop) prevyy: previous y (game loop) prevdir: previous direction
