Remove all "isinstance(conn, MTClientConnection)" tests from client handler to...

Remove all "isinstance(conn, MTClientConnection)" tests from client handler to make it unit-test-friendly: Client node does not have any listening socket, so there cannot be any (MT)ServerConnection instance used to reach handler. Also, Multi-Thread safety is not a runtime but a static criterion (ie, it is most likely a bug to use non-multi-thread-safe Connection subclasses in client). So this test is an always-true check, and can be removed.


git-svn-id: https://svn.erp5.org/repos/neo/branches/prototype3@307 71dcc9de-d417-0410-9af5-da40c76e7ee4