ipython/ipython — pull request #1934 by minrk (2012-06-13 02:28:20+00:00)
Title: Cell/Worksheet metadata

This implements a few forward-looking changes in the nbformat, which are unused.

closes #1915

* metadata dicts are attached to cells and worksheets
* restores collapsed flag to the nbformat - this change happened in the refactor, and was undocumented, and possibly accidental. But we should either document it or fix it, and this includes a fix.
* nbformat is a float, and the integer cast is used to denote readability. So we can potentially have 3.1 notebooks that must be readable by 3.0, even if not all capabilities are exposed.

These are proposed changes and meant for discussion, not to be merged immediately.