forbid building of the tty serial driver, as it is now extra broken
repair some debugging output errors.
add seperate rx/tx buffer flushing
add debug output for flushing requests
add function prototypes for rx/tx flushing
fix documentation of packet header
change behavior, header is now included in retrieved packet instead of being discarded, so the entire packet can be checksummed.
comment out some unused variables to shut the compiler up, until those functions are finished.  this file isn't used for much yet.
add new packet specs that might actually work
fix up hex string printing