Add an index on User.name

This is needed because this field is queried when the songs list
is being searched.

marietje/marietje/migrations/0007_user_name_index.py

@@ -0,0 +1,18 @@
+# Generated by Django 2.1.2 on 2018-10-28 16:22
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('marietje', '0006_user_blank_email'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='user',
+            name='name',
+            field=models.CharField(blank=True, db_index=True, max_length=30, verbose_name='name'),
+        ),
+    ]

marietje/marietje/models.py

@@ -58,7 +58,7 @@ class User(AbstractBaseUser, PermissionsMixin):
             'unique': _("A user with that username already exists."),
         },
     )
-    name = models.CharField(_('name'), max_length=30, blank=True)
+    name = models.CharField(_('name'), max_length=30, blank=True, db_index=True)
     email = models.EmailField(
         _('email address'),
         blank=True,