Add code to check if there is existing data before executing a bootstrap setup

apps/bootstrap/exceptions.py

@@ -0,0 +1,10 @@
+from __future__ import absolute_import
+
+
+class ExistingData(Exception):
+    """
+    Raised when an attempt to execute a bootstrap setup is made and there is
+    existing data that would be corrupted or damaged by the loading the 
+    bootstrap's fixture
+    """
+    pass