Behaviour is not defined for NEO but shutting down the client side seems
really bad (close is aliased to __del__).
Move no-op methods (close & cleanup) at file end, with not implemented ones.

git-svn-id: https://svn.erp5.org/repos/neo/trunk@1793 71dcc9de-d417-0410-9af5-da40c76e7ee4