Changed (selected) mission item color to primaryButton instead of buttonHighlight
Adjusted some colors for better contrast
Removed a few JavaScript exceptions caused by the order of object destruction

Signed-off-by: Tomaz Canabrava <tomaz.canabrava@intel.com>

Plus lots of other tweaks to ui for visuals

Passing parameters QVariantMap across C++ boundary was causing crashes
in Qt due to Qml array bugs. Referencing same Fact* across Qml boundary
in multiple QQuickWidgets caused jScript GC to crash.

Controls respect QGCPalette settings. Also added test window.