Improve output device support

[David Llewellyn-Jones]

Currently only the LED, PWMLED, Buzzer, Motor and Servo output device are implemented. GPIO Zero has support for several others and it would be great to have support for them here too:

1. LED
2. PWMLED
3. RGBLED
4. Buzzer
5. TonalBuzzer
6. Motor
7. PhaseEnableMotor
8. Servo
9. AngularServo