Add migration

production/migrations/0017_auto_20170914_2319.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.4 on 2017-09-14 21:19
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('production', '0016_remove_productionevent_noted_by_contributor'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='productionevent',
+            name='stream',
+            field=models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='events', to='production.ProductionStream'),
+        ),
+    ]