Healthx/griddle — pull request #14 by sdafforn (2012-12-10 12:47:12+00:00)
Title: Issue #10 - prohibit layering content items on top of one another.

Also some error message consolidation.

Some existing logic was altered to ensure that a container sitting directly on top of another container will generate an exception. Probably worth a review to verify that the old logic isn't needed elsewhere, the new change was solid, etc.