to be more robust and not depend on the ordering of the devices in
the techfile. The extraction method now keeps a mask of which
properties of the device (source/drain types, substrate type,
identifier type) have been found, and will look only for device
records that match what is known about the device. Added a device
identifier record which is the last record before parameters if the
record begins with "+". This allows marker layers to be placed
over a device such that it will extract with a different type.
This helps reduce the complexity of the techfile and allows
certain specialized devices like RF or ESD to be identified without
a separate layer type for the device.