Add missing args specification

Signed-off-by: Michal Čihař <michal@cihar.com>

weblate/accounts/management/commands/dumpuserdata.py

@@ -25,6 +25,7 @@ import json
 
 class Command(BaseCommand):
     help = 'dumps user data to JSON file'
+    args = '<json-file>'
 
     def handle(self, *args, **options):
         '''

weblate/accounts/management/commands/importuserdata.py

@@ -28,6 +28,7 @@ import json
 
 class Command(BaseCommand):
     help = 'imports userdata from JSON dump of database'
+    args = '<json-file>'
 
     def import_subscriptions(self, profile, userprofile):
         """

weblate/accounts/management/commands/importusers.py

@@ -25,6 +25,7 @@ import json
 
 class Command(BaseCommand):
     help = 'imports users from JSON dump of database'
+    args = '<json-file>'
 
     def handle(self, *args, **options):
         '''

weblate/lang/management/commands/checklang.py

@@ -24,6 +24,7 @@ from weblate.lang.models import Language
 
 class Command(BaseCommand):
     help = 'Checks language definitions against rst/csv file'
+    args = '<test-file>'
 
     def handle(self, *args, **options):
         '''