Fix #5812
Show an error message when creating a KML without 2 items at least
Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Converted Structure Scan to use CameraCalc such that it now works with
camera specs.

The ball pattern do not work in all cases, this new example add the basic video input with size information.

Change from BATT_VOLT_PIN to BATT2_VOLT_PIN.
Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Also fixed bug with ArduPilot guided waypoint write which would trash
existing mission.

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

Handle survey mode state

Also hand carried text to speech changes from Stable to master. Plus
unit tests for that.