add problem template field

problem/migrations/0003_problem_template.py

@@ -0,0 +1,22 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.9.12 on 2017-02-05 08:02
+from __future__ import unicode_literals
+
+from django.db import migrations
+import jsonfield.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('problem', '0002_auto_20170202_0826'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='problem',
+            name='template',
+            field=jsonfield.fields.JSONField(default={}),
+            preserve_default=False,
+        ),
+    ]