[devtools] restore i18n of string removed in 4001cfe2f44d Removing that string from the po files means that after running i18ncube against newer cubicweb, we lose the translation when running on older cubicweb's, which is probably not a good idea.

# -*- coding: utf-8 -*-
# copyright %(year)s %(author)s, all rights reserved.
# contact %(author-web-site)s -- mailto:%(author-email)s
#
%(long-license)s
"""%(distname)s schema"""