Fix 3D SIV Delay & Median Move

[amin1377]

• Add the scaled delay from the "koios_3d" benchmark into the 3D SIV-like architecture. The inter-die delay is calculated by multiplying the delay of the L4 segment by the ratio of the inter-die delay to the L4 delay of the Koios_3D architecture.
• Fix median/weighted median move to get the median layer of bounding boxes instead of pins (as it is the case for choosing x and y locations)

[amin1377]

2D Titan:

[vaughnbetz]

Add 3D results.

[vaughnbetz]

A few changes suggested, and please get the 3D data.

[vaughnbetz]

@amin1377 : is this one ready to merge?

[amin1377]

@vaughnbetz: I've just added more comments and rebased it with the master branch. Once the CI tests pass successfully, it'll be ready for merging.

[vaughnbetz]

Please merge once CI passes and the conflicts are resolved.