Added additional overlay color to material stuff and glstate

The overlay color should be used for overlays such as wireframe over flat shaded meshes.

closes #1369

git-svn-id: http://www.openflipper.org/svnrepo/OpenFlipper/branches/Free@16052 383ad7c9-94d9-4d36-a494-682f7c89f535

common/BaseObjectData.cc

@@ -174,6 +174,8 @@ void BaseObjectData::initializeScenegraphNodes() {
     materialNode_->set_base_color(colorV);
     materialNode_->set_color(colorV);
     
+    // We take the brightest color component for overlays to get best contrast
+    materialNode_->set_overlay_color(materialNode_->specular_color());
   }
 }