ROM dump + replace contents

[urish]

I wrote a few python scripts which can dump the ROM data directly from a given GDS file, and even replace the ROM content of in a GDS file. This allow you to "burn" new rom into a pre-hardened GDS in just a few seconds, meaning you don't have to rerun the compiler whenever you make changes to the content of your ROM.

You can find the scripts here: https://github.com/TinyTapeout/sky130-rom-experiments/tree/main/rom_utils