.. accidentally committed the first half of this update
alongside some changes to the documentation.
.. basically we now pass ANT messages on the stack rather than
as a pointer (fixes memory corruption issues).
.. the log file is explicitly opened and closed with status maintained
alongside that to ensure we only log messages when the logfile is open.
.. This is an alternative fixup to the fix proposed by Jon Escombe in
pull request #597.
ANT.cpp now emits a signal for each ANTMessage
ANTlocalController wires up this signal to a slot in ANTLogger which
writes the message to antlog.bin
Signed-off-by: dhague <darren.hague@fortybeans.com>