According to Spark docs: “The Core has 8 PWM pins: A0, A1, A4, A5, A6,
A7, D0 and D1.”
Merge branch 'pwm-pins' of https://github.com/Resseguie/spark-io into j5-examples
fixed PWM error message
updated pwm tests
Merge branch 'pwm-pins' of https://github.com/Resseguie/spark-io into j5-examples