DbDjango: method to checkpoint modules, to allow reloading Django

gramps/webapp/modules_checkpoint.py

@@ -0,0 +1,13 @@
+import sys
+
+class ModulesCheckpoint(object):
+    def __init__(self):
+        self.original = sys.modules.copy()
+        
+    def reset(self):
+        # clear modules:
+        for key in list(sys.modules.keys()):
+            del(sys.modules[key])
+        # load previous:
+        for key in self.original:
+            sys.modules[key] = self.original[key]