could have multiple ports of the same name. This problem had been
worked over before, but there was an indpendent mechanism producing
the same result for a completely different reason, caused by subcells
being much larger than the cookie-cutter extraction method's extraction
regions. Solved by tracking port names in a hash table and preventing
re-use. (2) ext2spice was producing "no such node" errors; like (1)
this had been previously worked on, and like (1) this mechanism was
independent. Problem came from not passing -1 to extHierSubstrate for
the non-arrayed dimension of a 1-dimensional array. Also: Removed
the word "fatal" from extraction error reporting, as nearly all
extraction errors are entirely benign. This should clear up confusion
among alarmed end-users.