Added breaking model definition to tests

Author: macro1

simple_history/tests/external/models/__init__.py

@@ -1,4 +1,18 @@
 from __future__ import unicode_literals
 
+from django.db import models
+from simple_history.models import HistoricalRecords
+
 from .model2 import ExternalModel2
 from .model4 import ExternalModel4
+
+
+class Poll(models.Model):
+    """Test model for same-named historical models
+
+    This model intentionally conflicts with the 'Polls' model in 'tests.models'.
+    """
+    history = HistoricalRecords()
+
+    class Meta:
+        app_label = 'external'