Add bool support to FactSystem

src/FactSystem/Fact.h

src/FactSystem/FactControls/FactCheckBox.qml

src/FactSystem/FactControls/FactTextField.qml

src/FactSystem/FactMetaData.cc

src/FactSystem/FactMetaData.h

src/FactSystem/SettingsFact.cc

src/FirmwarePlugin/APM/APMParameterMetaData.cc

src/FirmwarePlugin/PX4/PX4ParameterMetaData.cc

src/GAudioOutput.cc

src/GAudioOutput.h

src/QGCApplication.cc

src/QGCApplication.h

src/QmlControls/QGroundControlQmlGlobal.cc

src/QmlControls/QGroundControlQmlGlobal.h

src/SettingsManager.cc

src/SettingsManager.h

src/SettingsManager.json

src/comm/MAVLinkProtocol.cc

src/ui/MainWindow.cc

src/ui/MainWindow.ui