p5js/snowflake-pen - Refactor management of previous pen location
p5js/snowflake-pen - Refactor management of previous pen location

* Intention is to use fectors to facilitate rotations
* Now uses a simple boolean from the previous frame to track if pen was down or not.

brianhonohan/sketchbook,brianhonohan/sketchbook,brianhonohan/sketchbook