*animate chomps
*offset entire grid downwards to allow space for a header
*add images
*award points for stuff
*show score up the top
*animated points gaining (text fading out)
*touch events:
* touchstart: a finger is placed on a DOM element.
* touchmove: a finger is dragged along a DOM element.
* touchend: a finger is removed from a DOM element.
*parade must be at least 4
*cat can only eat food once, but can eat multiple foods in one go
*dont let chomp lines change dir (but parades can)
*allow reversing a line
*draw arrow for lines
*llama
*cats next to it can't move
*cat parades can include one (but only one).
*draw cats in centre of grid squares, not top left