Support baking contracts in the L1 genesis

[norswap]

The Optimism monorepo used to support to modes of "deploying" the rollup contracts to L1:

1. Deploying them to L1 directly
2. Deploying them to a temporary L1, then extracting data from the deployment artifacts, and baking the contracts into a new L1 genesis file.

In newer versions of the repo, option (1) has disappeared. That being said, the logic to deploy to the temporary or actual L1 should be almost entirely identical.

We need to support a generic version of (1) anyway, because we'll need supporting deploying to existing L1 (fixing the genesis file only works for nodes we spin ourselves).

The benefit of (2) is that if we're spinning new devnets often (e.g. to dev test a feature), then we cut off on the time (~30s?) it takes to deploy rollup contracts to L1. This is probably most relevant to people hacking on the node, which can use the built-in devnet from the Optimism repo instead.

Still, would be nice to support just in case, just probably not a huge priority.