keyboard and mouse events.
Added osgGA::EventQueue class to support a thread safe event queue and adaption
of keyboard and mouse events.
Removed osgProducer::EventAdapter as GUIEventAdapter replaces it.
Adapted osgProducer and examples to work with the new changes to osgGA.
methods, two that takes an index,two that takes a key value. Updated the ViewEventHandler
so the it now uses the getMatrixManipulatorWithIndex() method to avoid previous ambiguity.
Made Matrix be a typedef to either Matrixf or Matrixd. Defaults to Matrixf.
Converted the osgGA::MatrixManipulators and osgProducer::Viewer/OsgCameraGroup
across to using exclusively Matrixd for internal computations and passing betwen
Manipulators, Producer and SceneView. Note, SceneView still uses Matrix internally
so will depend on what is set as the default in include/osg/Matrix.
Added the ability to osgProducer::setDone/getDone(), kept done() as the
method that the viewer main loop uses for detecting the exit condition.
