=====XTension GPIO Kit API: Controlling GPIO outputs=====
GPIO Endpoints setup as outputs can be controlled with a simple GET request to the /api/gpio url:  http://xtgpio.local/api/gpio

To turn on gpio 3:
http://xtgpio.local/api/gpio?index=3&command=on

To turn off gpio 1:
http://xtgpio.local/api/gpio?index=1&command=off

Both index and command are required elements. Leaving any of them off will return an error instead. If you attempt to control a GPIO Endpoint that is lower than 0 or above the number of available GPIO endpoints an error is returned. If you try to control a GPIO channel that is not configured as an output an error will be returned.

Upon success the same json data as returned from the /api/data request is returned showing the new values if any that were changed by your command.

(BETA: Eventually the setvalue command will also be supported for endpoints like the servo and DAC outputs. This is not implemented yet in the current beta)