v0.2

Adds option to give serial DTR/RTS control signal sequence when connecting. If target device is equipped with appropriate circuitry, will auto-reset device into the bootloader.

Because of problems when attempting to flush the receive data buffers upon first opening the serial port (port.readable.cancel() never returns), some USB-UART adapters are now blocked from performing this behaviour. Currently, this only applies to adapters based upon the Silicon Labs CP2102N. If you experience the same issue with other USB-UART adapters (i.e. nothing happens when attempting to perform a programming action), please create a new Issue listing the adapter's manufacturer, model, and USB VID/PID.