delete GLView crash fix

fixed fog/background color, now not x2 amplified
fixed bug when no shadows enabled on start (sum with fog on geometry)

src/core/view/qglview.cpp

@@ -103,7 +103,6 @@ QGLView::QGLView(): OpenGLWindow(), renderer_(this), mouse(this) {
 
 QGLView::~QGLView() {
 	stop();
-	scene_->clear();
 	delete scene_;
 	delete default_camera;
 }