[Localization] 0.82 langpacks and root ownership correction

[Daniel Drake]

Hi,

The 0.82 language packs have a "find | xargs" at the end of the
installation script which attempts to correct root ownership on files
in /home/olpc/Activities
If there are no files with such misownership, it produces an error
which could lead the user to think that the installation failed.

Quick and easy fix: add the --no-run-if-empty argument to the xargs invocation

cheers,
Daniel