(epic) Work seamlessly with external gds

[marcolincs]

What is the feature being requested?

Different use-modes require different approaches. Below ranking the ones we are aware of from simpler to more complex. This case is to keep track of them all and continue discussion if these need to change/expand.

1. Feature Generalization: simple "plug-n-play" for ExternalComponent gds collection (should appear as a library as well)
2. Feature New: conversion from GDS to QGeometries (#23)
3. Research: how to best partition large layouts into sub-blocks
4. Research: enable easy manipulation of points/shapes from the converted GDS from step 2

Co-author: @priti-ashvin-shah-ibm

[priti-ashvin-shah-ibm]

This is about incorporating external gds files into Metal's format. This is ideal, but has not been addressed any more.