Adding support for controlling visual settings via environmental variables

and command line paramters.  Including support for stereo and stencil buffer.

src/osg/ColorMatrix.cpp

@@ -0,0 +1,22 @@
+#include <osg/GL>
+#include <osg/ColorMatrix>
+
+using namespace osg;
+
+ColorMatrix::ColorMatrix()
+{
+}
+
+
+ColorMatrix::~ColorMatrix()
+{
+}
+
+void ColorMatrix::apply(State&) const
+{
+//    std::cout<<"applying matrix"<<_matrix<<std::endl;
+
+    glMatrixMode( GL_COLOR );
+    glLoadMatrixf( _matrix.ptr() );
+    glMatrixMode( GL_MODELVIEW );
+}