Add ability to run mobymask-v2 stack with external optimism endpoint (#279)

* Set optimism geth endpoint from env file

* Set L1 account private keys from env

* Only deploy contract and generate invite in mobymask container

* Add readme for running mobymask v2 stack independently

* Modify mobymask container to stop running server and update readmes

* Check deployer account balance before deploying contract

* Fix for checking account balance before deploying

* Update readme description

* Update MobyMask repo tag in readme

Former-commit-id: 94e38ceaba

app/data/compose/docker-compose-fixturenet-optimism.yml

@@ -55,7 +55,7 @@ services:
     entrypoint: "sh"
     command: "/run-op-geth.sh"
     ports:
-      - "8545"
+      - "0.0.0.0:8545:8545"
     healthcheck:
       test: ["CMD", "nc", "-vz", "localhost:8545"]
       interval: 30s
@@ -77,7 +77,7 @@ services:
       - l2_accounts:/l2-accounts:ro
     command: ["sh", "/app/run-op-node.sh"]
     ports:
-      - "8547"
+      - "0.0.0.0:8547:8547"
     healthcheck:
       test: ["CMD", "nc", "-vz", "localhost:8547"]
       interval: 30s