mk: better when_platforms flags for flight and copter-motors-test
hx-stream: better haskell serial debugger

-- still not exactly anything brilliant
add hwf4-hxstream-test: testbed and code for hxstream framing in SiK
hxstream: updates

  efactoring, use dlists for efficiency, use ByteString.Word8.
hxstream (hs): wibbles.
hxstream: ivory implementation

  (still need to test).
hx-stream: library and test-harness.
hx-stream: update Ivory API.
ivory hx-stream: rewrite
flight: move uart creation out of gcsTower
ivory hx-stream: less polymorphic
ivory hx-stream: fix cabal & test executable
flight: initial datalink code (framing & trivial dispatch)
hs hx-stream serial-test build fixed
flight: datalink pads incomplete frames out with 0's
hs hx-stream: enhanced debugger for querying at codes
datalink: reject overruns
flight: run datalink loopback on uart5, which connects to radio on ioar
build: stabilize now called flight, empty flight-hil exists
move standalone_apahrs out of flight subdir