Update deleteTransaction definition in reference class.

It diverged at r2407.

git-svn-id: https://svn.erp5.org/repos/neo/trunk@2458 71dcc9de-d417-0410-9af5-da40c76e7ee4

neo/storage/database/manager.py

@@ -383,7 +383,7 @@ class DatabaseManager(object):
         temporarily data to a finished area."""
         raise NotImplementedError
 
-    def deleteTransaction(self, tid, oid_list):
+    def deleteTransaction(self, tid, oid_list=()):
         """Delete a transaction and its content specified by a given ID and
         an oid list"""
         raise NotImplementedError