#13 Add BlankBlock as a child exemplar of BlankBlock

[Anna Wojtowicz]

Currently, BlankBlocks don't have any child exemplars. I think ideally, you would want to be able to add a BlankBlock to a BlankBlock.

[Anna Wojtowicz]

The problem with this is that I can only add BlankBlocks as child exemplars of BlankBlocks to a finite depth from the Item side. I would think the only way to do this -- to a theoretically infinite depth -- is to make it happen in the UI side of things at the creation time of a BlankBlock.