the osgGA::AnimationPathManipulator to handle it.
Added a new Drawable::ConstAttributeFunctor and make the accept(PrimitiveFunctor)
be a const method so can disallows modification. Added Drawable::supports(...) methods
for each of the AttributeFunctor, ConstAttributeFunctor and PrimitiveFunctor so
that programs can querry whether it is possible to use functors with that object type.
the clash with the parameter type itself.
Addd a PER_PRIMTIIVE_SET handling to the existing PER_PRIMTIIVE code, this code
is still flacky though and needs a rewrite as it doens't handle all attributes or
the full consequences of per primitive and per primitive set bindings.
Converted AnimationPath so it is now subclassed from osg::Transform::ComputeTransfromCallback()
so that it can be directly attached to the scene to move objects about.
Changed the osg::SateSet::setGlobalDefaults() so that is sets GL_DEPTH_TEST
to ON.
Added guards and creation of default helper classes in osgGLUT::Viewer and
osgUtil::SceneView so that sensible defaults are used when no settings
are used of osg::State/StateSet,osgUtil::RenderStage/RenderGraph/CullVisitor.
