Added a missing migration (for review unavailable-period reason)

- Legacy-Id: 15402

ietf/review/migrations/0002_unavailableperiod_reason.py

@@ -0,0 +1,20 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.14 on 2018-07-23 15:11
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('review', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='unavailableperiod',
+            name='reason',
+            field=models.TextField(blank=True, default=b'', help_text=b"Provide (for the secretary's benefit) the reason why the review is unavailable", max_length=2048, verbose_name=b'Reason why reviewer is unavailable (Optional)'),
+        ),
+    ]