Interface display should clone widgets

[bgribble]

Graph-on-parent (#31) should work more like Max's Presentation Mode: widgets with a special property are cloned into the interface window and have a separate set of display parameters when in the interface display. This allows controls to be promoted to the front panel but still remain in the "main" patch.

[bgribble]

Clearing the milestone 0.05... I think this is for a future version. I thought it was necessary for meaningful implementation of #171, but now I don't think it is.

This will require some edits to sample patches, and the longer I wait the more to update... but good news/bad news: until they are edited, old patches won't have exported UIs, but at least they will be editable normally. The Interface layer will just be a normal layer that can go away.