feat(people): Add first user data fields

To support choices in CharFields, Django choices enums have been
backported by bringing in the source file from Django 3.0.3

See #1

people/migrations/0009_add_first_person_fields.py

@@ -0,0 +1,23 @@
+# Generated by Django 2.2.10 on 2020-02-21 16:49
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('people', '0008_order_answer_by_question'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='person',
+            name='age_group',
+            field=models.CharField(blank=True, choices=[('<=25', '25 or under'), ('26-30', '26-30'), ('31-35', '31-35'), ('36-40', '36-40'), ('41-45', '41-45'), ('46-50', '46-50'), ('51-55', '51-55'), ('56-60', '56-60'), ('>=61', '61 or older'), ('N', 'Prefer not to say')], max_length=5),
+        ),
+        migrations.AddField(
+            model_name='person',
+            name='gender',
+            field=models.CharField(blank=True, choices=[('M', 'Male'), ('F', 'Female'), ('O', 'Other'), ('N', 'Prefer not to say')], max_length=1),
+        ),
+    ]