magic database derived layout of a cell that declares GDS_FILE
but for which the GDS file referenced cannot be found or read.
This will produce an incomplete GDS file instead of an apparently
good and complete GDS file that actually contains bad data. Also:
Added new command "random" that allows a random seed to be set,
for use with the GDS output when writing a full dump of a GDS
file. Otherwise, the output prefixes are always the same, which
defeats the purpose of adding the random prefix.
bounding box of the selection (somewhat unuseful, especially as the
result gets absorbed by the tag callback), and "box select", which
sets the cursor box to the bounding box of the selection (much more
useful). Also corrected the "port" command so that the command
"port make" will search only for non-port labels.
enabling the "plow" command. At this time, however, not all
rules are being implemented correctly given the numerous changes
to the DRC handling since the last time "plow" was working. Fixes
are ongoing.