Added a second polygon. This polygon is updated from the first polygon at each mouse click and is what will ultimately be saved upon completion of drawing.

Update VTOL command text

Update message

Fix line back to home for VTOL takeoff

Adjust incoming message on channel 0

SDL2: Add missing Info.plist file for SDL2 framework.

Use single mavlink_status_t array

Update MAVLink parameter definitions for ArduSub

Add ArduSub firmware branding

ArduSub Safety Tab and Lights Tab

Switch ArduPilot setup pages to new SetupPage usage, plus vehicle branding

SDL2: Remove code signature file to (hopefully) fix macOS Sierra build.

Also added new FirmwarePlugin::brandImage support

Correct address of payload for Mav2

- fixes #4105

Update to SDL2 for Joystick Handling

Fix insert functionality after Survey Item