Tried to add jumps to level, but not seeing them yet.
Put more truck update stuff into function.
Now drawing jumps, but need to change draw order so truck appears behing them.
Looking into making a container hold the level and the truck, and need to change the truck container index as the truck moves up and down and then the draw order will be correct http://www.createjs.com/Docs/EaselJS/classes/Container.html
Made truck more oo, do level eventually also.
Made y position a truck member variable, limit pos_y to be onscreen.
Jumping with j key now works, though need to track key up/down so that a held key isn't interrupted by another key press.
Put level in own object, need to manage position of player on screen somewhere special, or get rid of variables and derive them every tick.
Crude jump detection and jumping when jumps are encountered.
3x5 pixel font, M,N, and Q are least legible.