mouse coords in osgGA::GUIEventAdapter, and ported osgGA camera manaipulators
to use the new normalized values.
Moved osgProducer across to tracking the window dimensions and ensure that the
internals values in osgProducer::EventAdapter are kept consistent. Moved
the warp pointer in Viewer across to using KeyboardMouse::positionPointer().
coord system.
Addition of ReadCameraConfigFile and WriteCameraConfigFile as a tempory
measure for implementing local a C++ read/write of the Producer::CameraConfig, this
will be removed once these implementations or similar have been moved to Producer.