Hoverboard guide clarification

[haroldina]

Added more descriptive text to the link to the hoverboard guide in Getting Started.

Added text above hall sensor configuration to indicate not to use that section if using an encoder added to the motor instead of the hall sensors. Added headings for "Hall Sensor Configuration" and "Calibration and Powering the Motor"

All to clarify these steps will not apply to users of hoverboard motors with added encoders, as is common for DIY force feedback controls.

[CLAassistant]

All committers have signed the CLA.