Set openImmediately flag to false

Added "false" to all the:

    "new SerialPort(comPort, {baudrate: 9600});"

to become

    new SerialPort(comPort, {baudrate: 9600}, false);

This will prevent the PORT from being opened and allow 'serialPort.open' to handle it

Resolves https://github.com/spark/spark-cli/issues/8