apt-get: update only required translations

apt Acquire::Languages can be set to declare which translations you want downloading. The variable "environment" specifies that apt should check $LC_MESSAGES. Here we go:

# eliminate any lists you might have
rm -rf /var/lib/apt/lists/
# set languages you need
echo 'Acquire::Languages { "environment"; "en"; };' > \
  /etc/apt/apt.conf.d/99lang
# update lists
apt-get update

If you need just English, it is okay just remove apt lists.