Use the Human Readable name not the machine name for content-type archives

Hi there,

I use the archive module to provide archives of different content-types on my website, however if I link to the specific page, it uses the machine name of the content type rather than the readable name.

eg on http://WhenTheTongueIsDone.net/archive/gracegems it lists the title as Archive - gracegems, rather than Archive - Grace Gems.

Attached is a patch which grabs the human readable name from the node_type table and uses that instead where it exists, and falls back to $type if it does not.