Implement changes suggested by @oskay in #50
* Start in center, and move absolute relative to center
* Add wait seconds block
* Add speed setting block
* Add absolute angle set
* Remove "reverse" option for move steps
* Add Block for moving to center (and left, top, bottom etc)
* Add "wash" block
* Add Motors off and Zero block
* Rephrase blocks to be more WCB specific and say "brush"
* Remove select tool block
* Break out rotate block into two rotate blocks with icons
Fix flipztoggle bit for pen height bug across firmware
TODO: Set this via version, if issue is better known