maint: use release instead of regenesis branches

ops: Build cleanups

feat: introduce the new BaseServiceV2 class 

Rewrites the message-relayer service to use BaseServiceV2. Significantly
reduces the footprint of the message-relayer and enforces stronger input
validation.

ProviderLike is too loose because it allows "any" to be ProviderLike.
This tightens the type to only include strings or ethers.Provider
objects.

Introduces the new BaseServiceV2 class to eventually replace the older
BaseService class. BaseServiceV2 includes many convenience features like
automatic environment variable and argv parsing.

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

Version Packages

develop => master

Changes our branching model to use release/ branches instead of
regenesis/ branches now that we no longer plan to perform any
regenesis-style upgrades. Using release/ branches will reduce confusion
from people who see a regenesis/ branch and assume (logically) that this
branch will result in a regenesis.

feat(sdk): update README and release 1.0.0

Updates the SDK README and includes a changeset that will trigger the
1.0.0 release of the SDK.

feat(sdk): support autogenerated docs

Adds a new command for automatically generating docs for the SDK. Will
be used by a new static hosted site to display SDK docs for users.

Fixes a typo in the docstring for the constructor of the
CrossChainMessenger class.

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.

Develop -> Master

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