This fixes the second problem described in https://github.com/FreeOpcUa/opcua-asyncio/issues/160#issuecomment-622985985

This fixes the first problem described in https://github.com/FreeOpcUa/opcua-asyncio/issues/160#issuecomment-622985985

Fix exception when disconnecting while not all Requests were processed.

This reverts commit 9ed0ca4b.

This reverts commit 99ee95d9.

Fixed comparison with literal. Comparision with a literal (str) should always be "!=" and not "is not".

Once a client is disconnected, the ThreadLoop it is running on is stopped. This applies to ThreadLoops the that are created in the Client's __init__ method, if not loop was passed as argument. Stopping the loop is now done within the delete method of the Client.

- Client.set_security
- Client.connect_and_get_server_endpoints
- Node.get_path
- Node.get_node_class
- Node.get_attributes

Cleans up dangling file descriptors that would otherwise be leaked

Similar to https://github.com/FreeOpcUa/python-opcua/pull/945
Small test: https://pastebin.com/SxUSnFi0