Add documents to decoders (#22)

* Add decoder documents support
* Use abstract model for Documents
* Increase version
* Code cleanup

ram/metadata/migrations/0012_alter_decoder_manufacturer_decoderdocument.py

@@ -0,0 +1,59 @@
+# Generated by Django 4.2 on 2023-09-30 21:54
+
+from django.db import migrations, models
+import django.db.models.deletion
+import ram.utils
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("metadata", "0011_company_slug_and_more"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="decoder",
+            name="manufacturer",
+            field=models.ForeignKey(
+                limit_choices_to={"category": "accessory"},
+                on_delete=django.db.models.deletion.CASCADE,
+                to="metadata.manufacturer",
+            ),
+        ),
+        migrations.CreateModel(
+            name="DecoderDocument",
+            fields=[
+                (
+                    "id",
+                    models.BigAutoField(
+                        auto_created=True,
+                        primary_key=True,
+                        serialize=False,
+                        verbose_name="ID",
+                    ),
+                ),
+                ("description", models.CharField(blank=True, max_length=128)),
+                (
+                    "file",
+                    models.FileField(
+                        blank=True,
+                        null=True,
+                        storage=ram.utils.DeduplicatedStorage(),
+                        upload_to="files/",
+                    ),
+                ),
+                (
+                    "decoder",
+                    models.ForeignKey(
+                        on_delete=django.db.models.deletion.CASCADE,
+                        related_name="document",
+                        to="metadata.decoder",
+                    ),
+                ),
+            ],
+            options={
+                "unique_together": {("decoder", "file")},
+            },
+        ),
+    ]