Slightly improve performance of collapsing NetEvent objects
Slightly improve performance of collapsing NetEvent objects

The NetEvent::find_similar_event method should limit its impact
on the netlist (and Nexus objects) by reducing the candidate event
list as it goes, instead of collecting data and testing later.

themperek/iverilog,CastMi/iverilog,CastMi/iverilog,themperek/iverilog,themperek/iverilog,CastMi/iverilog