Fix a bug where files with a .xml extension were being loaded a models instead of text files.
Update sandbox readme.
Add a button to the editor for creating an empty prefab.
Add prefabs (scene node classes) as a proper asset.
Fix a couple of bugs with serializing prefabs.
Have the drag-and-drop proxy element of a scene node from the scene editor's hierarchy panel store a pointer to the scene node.
Add the ability to create a prefab via the scene editor.
Add an error message when failing to load a prefab file.
Fix a couple of bugs in SceneNodeClassLibrary.
Add the ability to specify some options/flags when serializing a scene node.
Have SceneNodeClass stop serializing the ID and EditorMetadata component.
Add the ability to instantiate a prefab via the editor.
Fix a memory leak.
Fix a bug where a scene node with an ID of 0 was being added to the scene editor's hierarchy panel.