feat: allow multiple nationalities

Resolves #108

people/migrations/0052_allow_multiple_nationalities.py

@@ -0,0 +1,20 @@
+# Generated by Django 2.2.10 on 2021-03-19 15:39
+
+from django.db import migrations
+import django_countries.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('people', '0051_refactor_hardcoded_questions'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='personanswerset',
+            name='nationality',
+            field=django_countries.fields.CountryField(blank=True, default=[], max_length=746, multiple=True),
+            preserve_default=False,
+        ),
+    ]