replace calls to system millis() with overflow trap wrapper; make all temp vars holding times unsigned long
replace calls to system millis() with overflow trap wrapper; make all temp vars holding times unsigned long

hamishcunningham/fishy-wifi,hamishcunningham/fishy-wifi,hamishcunningham/fishy-wifi,hamishcunningham/fishy-wifi,hamishcunningham/fishy-wifi,hamishcunningham/fishy-wifi