back merged develop branch. apis updats
added switch. added ability to associated valves with the parent. tag. when the parent fires all its childern will also fire
Merge branch 'release/2.0.3' into develop

Conflicts:
	pychron/external_pipette/apis_manager.py
	pychron/extraction_line/extraction_line_manager.py
	pychron/extraction_line/valve_manager.py
	pychron/hardware/valve.py
	pychron/initialization_parser.py
	pychron/pyscripts/extraction_line_pyscript.py