not needed anymore because of autosave

Not needed anymore due to autosave

to protect against concurrent writes to the same file

- add a saving delay of 300ms
- save at most once every 2 seconds

This got introduced the the addition of the perf counter to the log.

Fixes the error:
unknown log message type 73

 * FW actuators fully on the entirety of front and back transition
 * back transition ramp up to full MC weight half way through back transition
 * increase maximum front and back transition times
 *  navigator don't reset transition altitude

When a FW/VTOL system detects a missing airspeed sensor, it produces an error message.
This patch uses the new relevant URLs in the PX4 documentation.

Fixes #4549

fix a spell error