Plus a large number of other changes to allow for orderly shutdown of
objects without crashes or asserts. This is need for unit tests to
create/delete global state around every test.

There appears to be a threading issue in qRegisterMetaType which can
cause it to throw a qWarning about duplicate type converters. This is
caused by a race condition in the Qt code. Still working with them on
tracking down the bug. For now we register the type which is giving us
problems here while we only have the main thread. That should prevent
it from hitting the race condition later on in the code.

This keeps TeamCity from hanging on a dialog box

Allows for UI unit tests to be written:
- Ability to respond to expected message boxes
- Ability to fail test if unexpected message boxes occurs

Allows you to run a single unit test from the command line

- allow unit tests to use QGCApplication
- clear global singletons for each unit test run

This disables Windows C Runtime assert dialogs from popping up.

Also commented out noisy serial link error output

Also fixed a number of other release build problems

Change so Waypoints are the same across maps, and offline waypoints get appeneded to the end of the MAV's waypoint list on connect

Added a qDebug() message handler for windows installs that have no debug helpers. Hunting bug in Mode change in UASView

Major cleanup of MainWindow constructor. All widgets have now the visible property set to false on its constructor

Switched from flite for speech on the Mac to built-in MacOSX speech synthesizer. Fixed build system for 64-bit builds (using official SDL.framework, and Qt frameworks).