Cherry pick virtual joystick fix from Stable

-Waddress-of-packed-member build error fix

VTOL Takeoff should be considered a transition to FW

VTOL Takeoff should be considered a transition to FW

Cherry pick joystick fixes from stable and fixup merge

Debian doc updates

Cherry pick joystick fixes from stable and fixup merge

Add return in CustomFirmwarePlugin::hasGimbal

Also fixed custom build

Since Ubuntu deprecated trusty, the TravisCI build will always fail
as it is unable to download packages against Ubuntu 14.

Add information for building doxygen documentation
on debian and fix for hardcoded path for dot.

remove warning caused build failure

Compiler warnings clean up

First run prompts

More warnings cleanup
Android fix
More
More
More
Fix typo
Update android compiler warnings
Fix android compiler warnings
More android compiler warnings

Modified support for multiple first run pages. Added first run for offline vehicle settings.

Toolbar: Visual tweaks

VIsual tweaks

Cherry pick stable fixes

FactMetaData: Add custom validator support

Add custom validator support

Cherry pick stable fixes

Turn warnings back on, silence warnings we can't fix

Introduce gimbal yaw visiblity setting

Added configurable value grid to toolbar

Added configurable value grid to toolbar

Fix VTOL hover determination

Fix VTOL hover determination

ToolStrip re-architecture for encapsulation and customization

Remove old action list code