Do not set active model from model list dialog

It's confusing and non-intuitive that saving the changes made to submodels opens the last
selected one. Furthermore we have the menu entries to open submodels.

common/project.cpp

@@ -335,7 +335,6 @@ void Project::ShowModelListDialog()
 
 	mModels = NewModels;
 
-	SetActiveModel(Dialog.mActiveModel);
 	gMainWindow->UpdateTitle();
 	gMainWindow->UpdateModels();
 }