Protocol: MotorControl delegates plunge to PipetteMotor.
Protocol: MotorControl delegates plunge to PipetteMotor.

It's more efficient and easier to follow if PipetteMotor gets
passed around instead of the axis.

OpenTrons/opentrons-api,Opentrons/labware,OpenTrons/opentrons-api,OpenTrons/opentrons_sdk,OpenTrons/opentrons-api,OpenTrons/opentrons-api,OpenTrons/opentrons-api