Refactored PX4 radio config to work with both PX4 and APM

- New mission command editor dialog
- New MissionCommands toolbox object to get command info
- Added APM mission item set

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

- Pervasive change to automatically connect to known board types
- Lots of additional changes along with this:
- More exposure of objects/properties to Qml
- Much restructuring in LinkManager and LinkManager clients

Restructured to better fit existing build structure

As this is no longer google specific, renamed everything google to qgc.

And name the target as the main app is now in its own sub project file.