Added kb_util.c/.h (the .h came from nanibox_util.h)
I converted the gps reading from the UART driver to the SERIAL driver, which does its own buffering.
It now parses the ublox message coming in, and passes it to the logger, so it's all getting written.
Updated kbb_viewer & KBB.py to show the GPS data. It's still only in GPS time & ECEF, which will need to get converted to UTC & LLA, but that's tomorrow.