* Bug: In CRL::ApDriver::DumpSegments(), when saving RoutingPads build
on Pin *not* at the top level (that is, Pin from an instance),
use the pin's orientation to choose the segment type.
* NORTH/SOUTH becomes a Vertical.
* EAST/WEST becomes an Horizontal.
Formerly, the segment direction was guessed only for the bounding
box, leading to segments in incorrect directions leading to DRC
errors (in nmigen/ALU16, net "b(10)").
* Bug: In CRL/symbolic/cmos/technology.py, forgotten import for
WarningMessage.