[trivial] Librarian upload shouldn't hang if passed an empty file
Patches applied:

 * stuart.bishop@canonical.com/launchpad--librarian--0--base-0
   tag of rocketfuel@canonical.com/launchpad--devel--0--patch-1712

 * stuart.bishop@canonical.com/launchpad--librarian--0--patch-1
   Raise ValueError instead of hanging if trying to add an empty file

 * stuart.bishop@canonical.com/launchpad--librarian--0--patch-2
   None should raise a TypeError

 * stuart.bishop@canonical.com/launchpad--librarian--0--patch-3
   Update daf's data migration script that triggered the problem on dogfood