extra pass to doing tri stripping in the osgUtil::Optimzer.
Added validity checks into osg::TexEnvCombine to catch eronous enumarant values.
Improved the efficient of CullingSet's handling of new transforms.
Added a copy shared subgraphs and subdivision code into osgUtil::Optimizer.
made ENABLE_ALL_CULLING enable all culling including the near and far plane.
DEFAULT_CULLING is now used for the default as uses the same original
values as ENABLE_ALL_CULLING once did - view frustum culling with near and
far culling. SceneView now uses DEFAULT_CULLING.
that they arn't created on the stack inappropriately.
Split the implemention of Matrix up so that it is a simple no referenced counted
class and can be safefly created on the stack. To support referenced counting a
seperate subclass now exists, this is RefMatrix which inherits from both Matrix and
Object.
