remove debugging print statements
firmware: look on all /dev/ttyACM* ports
Py/GTK app: give better error on GUI if Arduino comms fail
remove trailing whitespace. fix typo
Py/GTK app: expect new firmware
firmware: remove bit-flipping from ISR
firmware: take more LSBs on analog sampling
firmware: clean up comments
Py/GTK app: show sample rate when plotting
Qt app: remove system latency stuff - our sync model makes this unnecessary