Reflect changes to selection from outside in the outline view.

Doing this requires finding the controllers that are selected, which is a bit tricky. To do this, we create an array that includes all selectable controllers.
Made code look nicer.
Forgot to remove KVO Observer.
GLLTexture watches its file for changes.

It does so using NSFilePresenter and, additionally, kevents using GCD. This dual approach is necessary to get the file presenter goodness (which can see high-level operations like renames easily), but also file writes that do not use NSFileCoordination, such as those done by Photoshop.