gregbell/active_admin — pull request #1752 by randym (2012-11-02 11:34:20+00:00)
Title: Extracted duplicated download_format_links methods into helper

This serves two purposes. The first is to remove the duplicated code,
and the second is to stop using a hard coded list of default formats.
With this change, plugins can specify additional download formats so
long as the Mime type is registered.

Once this has been merged, I will release a gem that can be used to add xlsx downloads for collections.