* Add ChildDevice and ChildProtocolWrapper
* Initialize & update children
* Fix circular imports
* Add dummy_protocol fixture and tests for unwrapping responseData
* Use dummy_protocol for existing smartprotocol tests
* Move _ChildProtocolWrapper to smartprotocol.py
* Use dummy_protocol for test multiple requests
* Use device_id instead of position for selecting the child
* Fix wrapping for regular requests
* Remove unused imports
* tweak
* rename child_device to childdevice
* Fix import
