Add predeploys of Rollup factory contracts

[TucksonDev]

This PR adds instructions to predeploy the RollupCreator factory contracts through the genesis.json file. Creating all templates and the factory contract usually involves sending multiple transactions which slows down the starting process for the testnode environment. Predeploying these contracts should speed up the initialization process.

This PR only adds the factory contracts and doesn't modify the current initialization flow, since the pinned nitro-contracts version uses Create2 to deploy the factory contracts. Since these contracts are already deployed, the script only fetches the relevant contracts from the chain.

If in the future, contracts are deployed to different addresses (because the code is modified), the new predeploys file can be obtained by running the script added in this PR: OffchainLabs/nitro-contracts#403

Here are further improvement points, in case we want to continue down this path:

• Predeploy TokenBridge factory contracts (for the L2)
• Predeploy L3 rollup contracts
• Predeploy L3 TokenBridgeCreator contracts
• Predeploy the created Rollup (shouldn't speed up the process too much, since that's only a couple of transactions)
• Predeploy the created TokenBridge (same reasoning as above)