Add missing forum migration (and tiny translation fix)

forum/migrations/0003_auto_20170510_1754.py

+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('forum', '0002_auto_20170312_1753'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='forum',
+            name='edit_groups',
+            field=models.ManyToManyField(blank=True, default=[4], related_name='editable_forums', to='core.Group'),
+        ),
+    ]

locale/fr/LC_MESSAGES/django.po

@@ -1101,7 +1101,7 @@ msgstr "résumé"
 
 #: com/models.py:60 com/models.py:145
 msgid "content"
-msgstr "contenu de la nouvelle"
+msgstr "contenu"
 
 #: com/models.py:61 core/models.py:987 launderette/models.py:84
 #: launderette/models.py:109 launderette/models.py:145 stock/models.py:59