fixes, orval, downloader functioning again

backend/configuration/migrations/0002_alter_vatrate_rate.py

@@ -0,0 +1,26 @@
+import django.core.validators
+from decimal import Decimal
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('configuration', '0001_initial'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='vatrate',
+            name='rate',
+            field=models.DecimalField(
+                decimal_places=4,
+                help_text='VAT rate as percentage (e.g. 19.00 for 19%)',
+                max_digits=6,
+                validators=[
+                    django.core.validators.MinValueValidator(Decimal('0')),
+                    django.core.validators.MaxValueValidator(Decimal('100')),
+                ],
+            ),
+        ),
+    ]