ADSB server support provided through new ADSBVehicleManager implemenation

More work on contextual Plan tools

Fix center drag and split side

A contextual Land/RTL tool. Better waypoint line calc.

RTL is no longer part of Mission Settings

Advanced tuning hidden due to crash from Qt problem

Fix takeoff item insertion in plan creators

Only show split indicator on mission layer

More work getting _addMissionSetting right

Reduce height of items in combo dropdown

Reword to use sizeToContents on combos for flight mode channels

Update unit test for no auto takeoff item add

Fix handling of _addMissionSettings

Tweak combobox visuals

Remove unused code

Support for new TakeoffMissionItem and Takeoff Tool 

Comment out noisy warning

Fix crash caused by clear method not resetting internals correctly

PolyLine -> Polyline

Warn about glide slope altitudes

Polygon/Line tool name changes

Fixed unused variable

Fix Create Plan vertical spacing problem

Integrate Create Plan overlay in File DropPanel

Add simulateClick support

SectionHeader no longer set width automatically

Dynamic sizing of message buttons

Delete icon and Command Picker ui