Add bot level swapMotors override (for EggBot)
Heavily improve park position functionality (required for EggBot)
* Makes "zero" command set to park position
* Fixes centToSteps utility function to be in global scope, and adds argument to switch to maxArea percent (used only for park pos right now)
* Fixes park position to actually use absolute Max Area pos in steps
* Update return to clarify zero position and API doc
Freshen up readme a bit
Add some futureproofing removal of specifics, remove "alpha/beta" wording, etc.