Update config.xpresso.
update config.mbed.
Realized it makes more sense to tie XYZ enables together for mbed instead of XYA. An mbed user would be able to do filament changes by jogging the head to a new position, disabling A, changing filament, and re-enabling and jogging back. With XYA tied together they would lose XY position when changing filament.
Updated BOM to include new changes.