Signed-off-by: keenanjohnson <keenan.johnson@gmail.com>

 - fixes #8563

Signed-off-by: CarlOlsson <carlolsson.co@gmail.com>

This should ensure that the home position / altitude is only being used when valid.

The change is effective immediately so no reboot is required. This makes the whole configuration a lot easier.

The change is effective immediately so no reboot is required. This makes the whole configuration a lot easier.

 - GPS and battery were publishing at > 800Hz

 - update to latest sitl_gazebo

thread for offboard publishers, add asserts for topics to come up (simulation ready) and set mode and arming, use home_position topic as better indicator of when the simulation is ready, add more feedback to rosinfo, make timeouts meaningful (in seconds), add land and extended state values

This is important to have the probation times set up correctly and to silence land detected messages for systems that are not actually flying and just on the bench.