Connect to JTAG and Serial at the same time

On the current version of the 1-port bifferboards (using the new-style "missing pin" serial header - pictured here), the GND pin is shared by both the serial console connector and the jtag connector, making it impossible to connect to both simultaneuosly.

I made a simple adaptor using techniques similar to these, allowing me to connect to both connectors at the same time.