command line tool for creating outline summary

A while back I thought I saw a command line tool  that would create an hierarchical outline summary from tab-indented text... but I couldn't find it. So it was easier to just write this script than keep googling for it.

This is a command line tool that takes tab indented text and creates a formatted outline summary (based on the level of indentation).   I know that most word processors do outlines automatically, but I tend to prefer keeping all my notes in plain ASCII text.  This works in Linux and/or vim editor as well.

This works with Roman Numeral format (I A 1 a i), or the more modern Decimal formats (1, 1.2, 1.2.3).

Update 11/25/2015: I improved this script and uploaded to github:

https://github.com/sevkeifert/text-utils/blob/master/outline