Drawbot update: easier to configure!

It used to be to configure the drawbot you had to look for and change some pretty cryptic things in the code: X_SEPARATION, LIMYMIN, and LIMYMAX.  Worse, if you ever changed these values you had to re-flash your robot.  Maybe not a lot of work for an engineer, but too much for someone who wants it to just work.  So the latest version throws out all that and adds a new command.

CONFIG [Tx.xx] [Bx.xx] [Rx.xx] [Lx.xx];

Description: Sets the limits in the robot.

Input: the Top, Bottom, Right, and Left limits in the robot.  All measurements are in the current mode – you can switch to inches before calling config and it will compensate.  By default it expects centimeters (cm).  You can leave out any of the [values] and it will assume these numbers are unchanged.  You can rearrange them so long as the command starts with CONFIG and ends with a semi-colon.  You can leave out all options and get the current state of the limits.

Ouptut: The newest limits, the current feed rate, and the current acceleration.

Note: This command replaces LIMITS; as the output is the same.  The name has been changed because CONFIG; can be expanded on to add more features later.