[DO NOT MERGE] PoC predeploys

[TucksonDev]

[DO NOT MERGE]

PoC for adding a set of predeploy contracts to the genesis.json file. For each contract in the predeploys file, this script adds the following to the genesis.json file:

• an entry in the alloc object for the contract address
• the runtime bytecode of the contract with all the immutable variables whose values don't depend on the chain being deployed already replaced. For all chain-dependent immutable variables it can modify the bytecode based on the immutable references specified
• storage changes made on contract initialization

Current genesis.json file is based on Arb1 (chain id 42161) to verify that contract bytecodes match the ones on-chain.