Set the default setting of LineWidth to 2.0 to ensure that old default behavior

is maintained.

src/osgFX/Cartoon.cpp

@@ -272,7 +272,7 @@ namespace
 Cartoon::Cartoon()
 :    Effect(),
     _wf_mat(new osg::Material),
-    _wf_lw(new osg::LineWidth),
+    _wf_lw(new osg::LineWidth(2.0f)),
     _lightnum(0)
 {
     setOutlineColor(osg::Vec4(0, 0, 0, 1));