ipython/ipython — pull request #2977 by robyoung (2013-02-24 21:03:06+00:00)
Title: Add hierarchical notebook list.

Add the ability to save notebooks in subdirectories under the main notebook directory. Slashes in the notebook name are converted to directory separators, the notebook file name is the last part of the notebook name. On the notebook list view directories are displayed like notebooks but with a + or - to their left. When clicked they expand to show their contents.