About/Credits dialog

[GoogleCodeExporter]

The program should include a simple "about" and/or "credits" dialog.  This
could on the menubar by itself, or under the "File" menu, which shouldn't
really be named "File" anyway.

It should include:

* program name
* current version
* project URL
* project email address
* list of sponsors, w/ links
* list of contributors

Original issue reported on code.google.com by [email protected] on 26 Mar 2008 at 3:06