if a GDS (CIF) layer is dependent on, and only on, a templayer or
layers that get hierarchically processed, it will not get added to
the list of layers needing hierarchical processing, and therefore
end up not being generated in the output.
options "text", "port", and "noport" in the techfile. The
incorrect interpretation was preventing backwards compatibility,
such that ports would not be output on GDS layers if the "port"
option was not used.
"port" and "noport" in the cifoutput section to distinguish
between layer:purpose pairs for port text vs. other kinds of
text. This allows a closer correspondence between GDS read and
write. Note that the port writing is currently only in the GDS
write routine, not in the CIF routine.
Tim Edwards