As a Google Summer of Code Intern, I have been working on the Mass
Migration tools project  for Wikimedia. We are now ready with a minimal
working product . The tool helps translators and translation
administrators import the old translations into the Translate Extension .
An instance of the same has been set up on labs. You can find some useful
instructions on the main page .
Please test the tool and report bugs/suggestions using the link provided on
the main page itself. You can have a look at the tracking bug  to check
already reported bugs.
Looking forward to hearing from you! Cheers.
GSoC Intern | Wikimedia