flattening based on cells which have a property "flatten". Also:
Modified the DEF read and write to convert DIEAREA into a
FIXED_BBOX property. This solves issues with placing of components
from DEF, when those components may not have have come from place &
route and may not have P&R bounding boxes. Also: Fixed the
documentation for the "dump" command, which was missing the optional
orientation in the description.