This is not an addon, it is a listing of color codes of use to those writing addons.
This is a list of the default colors for all of the chat channels, usable with any of the assorted API functions that set the color of wow interface elements.
The zip file contains a Microsoft Excel file and an CSV file, both contain the same data.
I needed this list and couldn't find it, so I created it. Posting here in case someone else needs it as well.