GrampsLocale: Don't set to 'C' if LANG is en_US

Not required, Gtk has an 'en' translation

Ref. http://www.gramps-project.org/bugs/view.php?id=6867

svn: r22710

gramps/gen/utils/grampslocale.py

@@ -437,8 +437,7 @@ class GrampsLocale(object):
                 lang = '.'.join((check_lang[0], 'UTF-8'))
 
         os.environ["LANG"] = lang
-        os.environ["LANGUAGE"] = ':'.join(['C' if l in ('en', 'en_US') else l
-                                           for l in self.language])
+        os.environ["LANGUAGE"] = ':'.join([l for l in self.language])
 
         # GtkBuilder uses GLib's g_dgettext wrapper, which oddly is bound
         # with locale instead of gettext. Win32 doesn't support bindtextdomain.