Supported cases that are not tested by the test logs

[hamishwillee]

I wrote a script to gather the descriptions, status and reason strings from across a specified directory. This was run on the private 3DR test data. The following strings did not show up in the tests but are present in the code.

Whether this is a problem or not, or one we can fix I don't know - but providing in case we can generate such logs.

Battery

• Fail: Battery failsafe event received

Compass Offsets

• Fail: Compass offset parameter set seen/set
• Warn: Compass offsets in parameters are zero

Brownout

• Warn: Altitude never changed

Crash Test

• Fail: Vehicle evaluated itself as crashed
• Warn: Vehicle's attitude never updated

Compass Vector Length

• Warn: Compass Vector Length below threshold

Arming Checks

• Fail: Some of the arming checks were disabled when the craft was armed

Good GPS

• Tests on: velocity, terrain_alt_variance for both "exceeds fail threshold" and "exceeds warn threshold"
• "never updated" (e.g. * Warn: [variance] was never updated)
• warning: EKF flags were never updated