Document editor/naming/scene_name_casing setting

Moved definitions of editor related project settings to `editor/register_editor_types.cpp` to make documentation work.

editor/editor_node.cpp

@@ -6579,7 +6579,6 @@ void EditorNode::_feature_profile_changed() {
 }
 
 void EditorNode::_bind_methods() {
-	GLOBAL_DEF(PropertyInfo(Variant::INT, "editor/naming/scene_name_casing", PROPERTY_HINT_ENUM, "Auto,PascalCase,snake_case"), SCENE_NAME_CASING_SNAKE_CASE);
 	ClassDB::bind_method("edit_current", &EditorNode::edit_current);
 	ClassDB::bind_method("edit_node", &EditorNode::edit_node);