implements a method for handling ports in a subcircuit that have different
port names and indexes but are shorted together. "none" is the default
and backwards-compatible behavior that merges ports together, which will
often cause one of the ports to be optimized out of the netlist. "resistor"
will separate the port names with a 0-ohm ideal resistor. "voltage" will
separate the port names with a 0-volt voltage source. This should work
well for simulation and potentially for LVS, although its impact on LVS
has not been fully investigated.
Tim Edwards