More work getting _addMissionSetting right

Update unit test for no auto takeoff item add

Fix handling of _addMissionSettings

Support for new TakeoffMissionItem and Takeoff Tool 

PolyLine -> Polyline

Polygon/Line tool name changes

Fixed unused variable

Integrate Create Plan overlay in File DropPanel

New centered PlanEditToolbar

Don't set wizard mode on regular waypoints

Fix save state checks. Show overlay on New.

Minimum transect spacing of 0.5 meters

Remove unused variable

Wizard Mode for Create Plan

New Create Plan support

Button name changes

Corridor edit toolbar

New editing tools support

Rework presets

More work on mission item indicators

Fix SplitSegment insertion

Handle cross fact update internally

Don't query terrain if no location

Use new SplitIndicator control

Allow split of current segment

Correctly handle command changes from no-coordinate item to coordinate item

Remove unnecessary signaling

Use QmlObjectListModel::begin/endReset to keep Qt from blowing it's brains out with too many updates

Remove testing ifdef

Directions arrows in Fly View

Fix initial load for Plan view

Fix missing waypointLinesChanged signal. Remove unnecessary directionArrowChanged signal.

More work on direction arrows

New MapLineArrow control