in create_user mgmt command, use settings.LANGUAGE_CODE instead of en-us.

Fixes the create_user admin command, which was creating user accounts
with a potentially invalid language preference.

JIRA: FOR-532

common/djangoapps/student/management/commands/create_user.py

 from optparse import make_option
+
+from django.conf import settings
+from django.contrib.auth.models import User
 from django.core.management.base import BaseCommand
+from django.utils import translation
+
 from student.models import CourseEnrollment, Registration, create_comments_service_user
 from student.views import _do_create_account, AccountValidationError
-from django.contrib.auth.models import User
-
 from track.management.tracked_command import TrackedCommand
 
 
@@ -36,7 +39,7 @@ class Command(TrackedCommand):
                     default=None,
                     help='Name, defaults to "user" in the email'),
         make_option('-p', '--password',
-                    metavar='NAME',
+                    metavar='PASSWORD',
                     dest='password',
                     default=None,
                     help='Password for user'),
@@ -51,7 +54,6 @@ class Command(TrackedCommand):
                     default=None,
                     help='course to enroll the user in (optional)'),
         make_option('-s', '--staff',
-                    metavar='COURSE_ID',
                     dest='staff',
                     default=False,
                     action='store_true',
@@ -74,6 +76,11 @@ class Command(TrackedCommand):
             'honor_code': u'true',
             'terms_of_service': u'true',
         }
+        # django.utils.translation.get_language() will be used to set the new
+        # user's preferred language.  This line ensures that the result will
+        # match this installation's default locale.  Otherwise, inside a
+        # management command, it will always return "en-us".
+        translation.activate(settings.LANGUAGE_CODE)
         try:
             user, profile, reg = _do_create_account(post_data)
             if options['staff']:
@@ -87,3 +94,4 @@ class Command(TrackedCommand):
             user = User.objects.get(email=options['email'])
         if options['course']:
             CourseEnrollment.enroll(user, options['course'], mode=options['mode'])
+        translation.deactivate()