add method to clear node manager

git-svn-id: https://svn.erp5.org/repos/neo/branches/prototype3@447 71dcc9de-d417-0410-9af5-da40c76e7ee4

neo/node.py

@@ -162,3 +162,8 @@ class NodeManager(object):
     def getNodeByUUID(self, uuid):
         return self.uuid_dict.get(uuid)
     
+    def clear(self, exclude_node_type=None):
+        for node in self.getNodeList():
+            if exclude_node_type is not None and \
+                   node.getNodeType() != exclude_node_type:
+                self.remove(node)