Cleans up a bunch of configuration in `ops/`, in preparation for switching most of our build configuration to CircleCI. Changes include:

1. Removing the "builder image" concept in favor of a single multi-target Dockerfile. Once this goes live on CircleCI, we'll be able to leverage Docker Layer caching more effectively.
2. Fixes the nightly build, which is currently failing on the legacy batch submitter.
3. Removes the legacy rpc-proxy since it isn't used anywhere anymore.
4. Re-enables CODEOWNERS.
5. Removes the `docker-compose-nobuild.yml` file, since the main `docker-compose.yml` file now supports images and builds.

Meta:

- Fixes ENG-1838

refactor(tests): migrate from smock v1 to smock v2

indexer: fix metrics, reduce DB load

changeset: cleanup packages

linting: speed up with new config

https://github.com/typescript-eslint/typescript-eslint/issues/3528

Cuts the run of linting from 68s to 44s on my local machine
with `yarn lint` at the root of the repo

This commit adds all packages in the `go` directory
to the changesets packages so that they don't need
to be added individually. It also removes `specs` since
that directory no longer exists.

Version Packages

Develop -> Master

batch-submitter: Remove bad changeset, remove old build

feat: indexer service to replace etherscan dependency

Develop -> Master

cleanup(contracts): remove unused code

Develop -> Master

l2geth: Add support for system addresses

Adds support for system addresses.

To deploy to a system address, the deployer must either be in the list of hardcoded addresses described in `SystemAddressDeployers`, or be specified via the `SYSTEM_ADDRESS_0_DEPLOYER`/`SYSTEM_ADDRESS_1_DEPLOYER` environment variables. The hardcoded system addresses deployers will always override those placed in the environment, so specifying the `SYSTEM_ADDRESS_*` env vars on mainnet, Kovan, or Goerli is a no-op. The env vars are available primarily for testing purposes.

The contract deployment **must** be the first transaction from the deployment address - i.e., it must have nonce zero.

In order to make the tests work, I had to change the integration tests chain ID to no longer conflict with Goerli. The new integration tests chain ID is `987`.

Co-Authored-By: @inphi

Removes functions and constants that are not used in the contracts
package. Also removes export from interfaces that are not being imported.

fix(ct): remove yargs as unused dep

feat(sdk): add fn to wait for message status

feat: remove packages/batch-submitter

Removes yargs as a dependency from the contracts package since it wasn't
being used. Always good to cut unused dependencies.

Adds a function to the SDK (waitForMessageStatus) which will wait until
the status of a particular message matches the target status.
waitForMessageStatus also handles certain special cases where different
status messages are incompatible (e.g., the RELAYED and
FAILED_L1_TO_L2_MESSAGE status for L1 to L2 messages). Useful to avoid
including looping logic in your own application.

fix(bridge): Corrected a comment

fix(rhc): fix dockerfile bug

contracts: fetch batches hardhat task

increase coverage of contracts package

This commit increases the statement and branch coverage of the contracts
package. More specificall the contracts that were covered are:

- AddressDictator
- ChugSplashDictator
- L1CrossDomainMessenger
- L1StandardBridge
- CanonicalTransactionChain
- ChainStorageContainer
- StateCommitmentChain
- L2CrossDomainMessenger
- L2StandardBridge
- WETH9
- Lib_OVMCode
- Lib_RLPWriter
- Lib_SecureMerkleTrie
- Lib_Buffer
- Lib_MerkleTree