More code documentation

doc/Doxyfile

doc/graphs.graffle

doc/header.html

doc/links.md

doc/links.svg

doc/vehicleMgmt.md

src/AnalyzeView/MAVLinkInspectorController.h

src/Camera/QGCCameraControl.h

src/Camera/QGCCameraIO.h

src/Camera/QGCCameraManager.h

src/Joystick/Joystick.h

src/Joystick/JoystickManager.h

src/Joystick/JoystickSDL.h

src/Settings/AppSettings.h

src/Settings/AutoConnectSettings.h

src/Settings/BrandImageSettings.h

src/api/QGCCorePlugin.h

src/api/QGCOptions.h

src/api/QGCSettings.h

src/ui/MainRootWindow.qml