Add migration script to remove every duration_old.

fkbeta/fk/migrations/0005_remove_duration_old.py

@@ -0,0 +1,27 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.7 on 2019-01-01 11:14
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('fk', '0004_is_filler_explained'),
+    ]
+
+    operations = [
+        migrations.RemoveField(
+            model_name='scheduleitem',
+            name='duration_old',
+        ),
+        migrations.RemoveField(
+            model_name='video',
+            name='duration_old',
+        ),
+        migrations.RemoveField(
+            model_name='weeklyslot',
+            name='duration_old',
+        ),
+    ]