i18n: Made `N_()` a real no-op marker, and don't accept (and substitute) keyword arguments. This is consistent with the Python documentation <http://docs.python.org/library/gettext.html#id5>.
i18n: Made `N_()` a real no-op marker, and don't accept (and substitute) keyword arguments. This is consistent with the Python documentation <http://docs.python.org/library/gettext.html#id5>.

Part of #9341.


git-svn-id: f68c6b3b1dcd5d00a2560c384475aaef3bc99487@9705 af82e41b-90c4-0310-8c96-b1721e28e2e2

moreati/trac-gitsvn,exocad/exotrac,moreati/trac-gitsvn,dafrito/trac-mirror,dafrito/trac-mirror,dafrito/trac-mirror,moreati/trac-gitsvn,exocad/exotrac,exocad/exotrac,moreati/trac-gitsvn,dafrito/trac-mirror,exocad/exotrac