ArduPlane: Remove some geofence logic from ArduPlane

ArduPlane: Refactor action and mode return implementation

ArduPlane: Use polyfence to find the return point.

AC_Fence: Add fence floor breach checks and calculations

AC_Fence: Add event logging to enable/disable of fence floor

AC_Fence: Adjust sys_status reporting to look at total fence count

AC_Fence: Make retrieving of the return point accessible

AC_Fence: Check whether fence is enabled or autoenable is set for arming checks

Checks whether the fence is currently enabled OR if the fence is intended to be enabled automatically.
These checks are used to find out enabled fences, or prearm checks

AP_Arming: Use auto enable flag to arm fence only when armed (as per enum)

AP_Arming: Config defines are not available in AP_Arming

Since config definitions are not available in AP_Arming, we can still rely on singleton access of the AC_Fence object.

AP_Arming: Perform fence checks for all vehicles

GCS_MAVLink: Add disabling of fence floor only, per mavlink spec

GCS_MAVLink: Cannot enable a fence if the fence is not present

Autotest: Remove ties to mavlink FENCE_ACTION

Autotest: Add ArduPlane autotest to test ceiling and floor

Adds a test to ensure the vehicle reverts to RTL when breaching a ceiling or floor.

Autotest: Progress the test once we reach takeoff complete and fence enable

Autotest: Use RC_OPTION for Aux Switch functionality

Autotest: Enable fence last

ArduPlane: Remove missed geofence logic

Adds corrections to enabling fence using aux function.
Correctly test fences statically. Only uploaded fences can be checked using a fence file, so we check those first. Then we add steps to check tin can, max and minm all set the fence as present, as expected.
Plane will support MAV_PROTOCOL_CAPABILITY_MISSION_FENCE, so we assert that it does support it.
To test ceiling and floor, leverage some existing functions for takeoff, change altitude and land. Check for respective breach.
Add a floor breach check to copter.

I'm not sure if a better fix would be to remove the set_parameter() call

…many users.

Talked to Randy about this. The consensus was not to delete the parameter

…our times

…eoff and landing

This should not be required in the future, please fix this and revert this commit

Fix comments

…floor

Adds tests for:
* Testing auto-enable disabled (when no autoenabling of the fence is required)
* Test auto-enabled always after takeoff (when takeoff complete condition met)
* Test auto-enabled disable floor only (when land sequence begins)
* Test auto- on arm/disarm (when vehicle is armed/disarmed)
* Tests ability to land when fence is breached

…test

…aram

…geofence

…_Fence

…across all vehicles now

…cross all vehicles now

…t been auto disabled

This appears to be another case of the fence state carrying over from one test to another. Disabling the fence at the end of the test appears to have fixed this problem

ArduPlane: Move auto enabling code to common fence library

…ameter

Addresses comments made in review, removes the FENCE_AUTOENABLE param for copter.
No param means no tests required.

… disabled while under action

…ched

AutoTest: Adds test for fence breach switching to guided mode when no fence return point is present. In upstream, this results in a vehicle fly-away.