Always how command description. Better support for VTOL Takeoff. New help text for altitude on Land commands.

Change some descriptions to be more understandable/correct. Change some Heading->Yaw labels. Use new isLandCommand setting.

Survey And Corridor now share same transect generation code. Better unit tests for both with more coverage.

Correct handling of terrain ready when loading back from file

Unit Test for Survey command sequence generation

Major rewrite of Survey generation for simplicity. Also includes support for CONDITION_GATE.

Unit test for mission transfer error string checking

Much better error reporting for Mission transfer errors

Plan: Add support for takeoff item required

Shape file examples for testing

Wizard mode should be off for loaded items

Clear wizard mode when loading from file

Fix alternate transect support

Fix ArduPilot fake home position handling

Mavlink terrain protocol support

Added compiler switch for developers to generate survey preset default json files for use as built-in survey presets in custom builds

Support for built-in preset delete prevention

Fix load order so isManualCamera returns correct value

Show errors from preset load failures

Fix Done Tracing <-> Done PolyFoo in wizard relationship

Avoid arrow positioning with take item

Fix typo

Track trace mode in polygon so we can use it to exit wizard mode

Fix current item updating after delete

Not setting _isIncomplete correctly was causing crash

Fix Plan insert Takeoff/Land for correct enable state and insert into correct place. 

Plan: Make PX4 VTOL takeoff work like fixed wing