- Central widget no longer stacked. Views are added/removed to layout
to switch view
- Dock Widgets are globals with single instance of each type
- Both central views and dock widgets are just-in-time created saving
lots of memory

I initially change version numbers incorrectly. Should have left stable
at 2.1 and only bumped Developer to 2.2. This leaves Stable at 2.2 and
Developer at 2.3.

Prepping for stable 2.2 release

Change of name for diydrones fork of QGroundControl to APM Planner 2.0, per Chris Anderson and Craig Elder

HIL config improvements, fixed confusion about which dock widget is part of which view, main window behaving now

Started adding numbers to QGC_APPLICATION_VERSION for development builds, since dev builds need the config file wiped out for UI changes to be visible

Minor cleanup, fixed a bug where the serial port would not connect on first application launch on Linux