This stops us tracking formats-written in two places.
The Write() method will now emit formats as required and set the relevant bit in the backend-owned bitmask of formats sent.
this sets the logging rate max when disarmed. In combination with
LOG_DISARMED=3 it gives a very nice setup to get always on logging
with very little addition to the log sizes. It is particularly useful
in combination with LOG_REPLAY=1
mavlink log reads fail randomly, and you end up with a very large number
of log files as we keep closing logs off and then discovering we should
be logging
this prevents logging garbage for strings that are shorter than the
length specifier (eg. 'Z'). This assumes we will not want to log
binary data as strings
add support for log time to block logger
refactor rotation into backed. Don't start logs when erasing
correct log start logic
separate read and write points so that requesting log information does not corrupt the current log
when starting a new log stop logging first
clear the write buffer when starting a new log
insert utc time when requesting info for the current log
stop logging and request formats again when starting a new log
cope with erase happening while we are logging
keep pushing out startup messages even when format messages are done
don't log to the gcs in the io thread
don't start new logs in the io thread
don't validate logs while erasing
flush logs when stopping logging
account for page header when calculating logs sizes
don't return data when asked for more data than in the log
optimize locking and use separate semaphore to mediate ring buffer access
stop logging when the chip is full and send a notification
calculate logs sizes correctly even when they wrap
read log data correctly even when it wraps
add stats support to block logger
reset dropped when starting a new log
fail logging when the chip is full
refactor critical bufferspace checks
increase messagewriter budget to 250us and to 300us for FMT
Instead of creating a MessageWriter explicitly to log uploaded missions
we fiddle the state of the one stored in the startup message writer.
This has the advantage of being much more likely to log the entire
mission (as the buffer constraint is removed), and with the addition of
a time-remaining check much less likely to cause a timing glitch.
