FEAT: Initial work on revision history for assets

The revision history for individual items mostly works, though it shows database ID where it should show asset ID. Recent changes feed isn't yet done.

assets/models.py

@@ -6,6 +6,10 @@ from django.urls import reverse
 from django.db.models.signals import pre_save
 from django.dispatch.dispatcher import receiver
 
+from reversion import revisions as reversion
+from reversion.models import Version
+
+from RIGS.models import RevisionMixin
 
 class AssetCategory(models.Model):
     class Meta:
@@ -30,7 +34,8 @@ class AssetStatus(models.Model):
         return self.name
 
 
-class Supplier(models.Model):
+@reversion.register
+class Supplier(models.Model, RevisionMixin):
     name = models.CharField(max_length=80)
 
     class Meta:
@@ -55,7 +60,8 @@ class Connector(models.Model):
         return self.description
 
 
-class Asset(models.Model):
+@reversion.register
+class Asset(models.Model, RevisionMixin):
     class Meta:
         ordering = ['asset_id_prefix', 'asset_id_number']
         permissions = (