Fix #381 -- Add location field (#398)

* add location field

* rearrange the display order

src/pretix/base/migrations/0061_event_location.py

@@ -0,0 +1,21 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.10.5 on 2017-02-01 04:31
+from __future__ import unicode_literals
+
+from django.db import migrations
+import pretix.base.i18n
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('pretixbase', '0060_auto_20170113_1438'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='event',
+            name='location',
+            field=pretix.base.i18n.I18nCharField(blank=True, max_length=200, null=True, verbose_name='Location'),
+        ),
+    ]