Get paths for multiple keys

[GoogleCodeExporter]

I am retrieving thumbnails from MogileFS, usually a few hundred at the
time. So far I handle this in the application, by tapping directly
into the database. I get all fids using one query, which include a
verified list of alive hosts. I don't really find this to be an
elegant solution, particulary since I need to verify host status in my
application. 

I would like to be able to retrieve paths for multiple fids using tracker.

Original issue reported on code.google.com by [email protected] on 20 Mar 2011 at 12:49