add merged migrations

core/migrations/0020_merge_20191006_1444.py

+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.5 on 2019-10-06 07:44
+from __future__ import unicode_literals
+
+from django.db import migrations
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0017_vacancy_amount'),
+        ('core', '0019_merge_20191006_0852'),
+    ]
+
+    operations = [
+    ]