proto2lef: convert VLSIR layout proto to LEF description#31

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growly wants to merge 3 commits intodan-fritchman:mainfrom

growly:proto2lef

Commits on Dec 2, 2022

just give me a lef
growly
committed

Commits on Dec 3, 2022

make "Invalid un-named layer for LEF export" slightly more descriptive
growly
committed

Commits on Dec 4, 2022

load layer names when importing them from the pb tech file
growly
committed