python//qmp.py: use True/False for non/blocking modes
python//qmp.py: Define common types
python//qmp.py: re-absorb MonitorResponseError
python//qmp.py: Do not return None from cmd_obj
python//qmp.py: add casts to JSON deserialization
python//qmp.py: add QMPProtocolError
python//qmp.py: assert sockfile is not None
python//machine.py: remove logging configuration
python//machine.py: Fix monitor address typing
python//machine.py: reorder __init__
python//machine.py: Don't modify state in _base_args()
python//machine.py: Handle None events in event_wait
python//machine.py: use qmp.command
python//machine.py: Add _qmp access shim
python//machine.py: fix _popen access
python//qtest.py: Check before accessing _qtest