feat(op-stack/forced-withdrawal): Explanation

op-stack/forced-withdrawal/.env.example

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+L1URL=<<< L1 URL goes here >>>
+L2URL=<<< L2 URL goes here >>>
+PRIV_KEY=<< private key goes here >>>
+OPTIMISM_PORTAL_ADDR=<< address of OptimismPortalProxy >>

op-stack/forced-withdrawal/.gitignore

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+node_modules
+
+#Hardhat files
+cache
+artifacts
+
+node_modules
+
+#Hardhat files
+cache
+artifacts

op-stack/forced-withdrawal/contracts/Greeter.sol

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+//SPDX-License-Identifier: Unlicense
+pragma solidity ^0.8.0;
+
+import "hardhat/console.sol";
+
+
+contract Greeter {
+  string greeting;
+
+  constructor(string memory _greeting) {
+    console.log("Deploying a Greeter with greeting:", _greeting);
+    greeting = _greeting;
+  }
+
+  function greet() public view returns (string memory) {
+    return greeting;
+  }
+
+  function setGreeting(string memory _greeting) public {
+    console.log("Changing greeting from '%s' to '%s'", greeting, _greeting);
+    greeting = _greeting;
+  }
+}

op-stack/forced-withdrawal/hardhat.config.js

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+require("@nomiclabs/hardhat-waffle");
+require('dotenv').config();
+
+// This is a sample Hardhat task. To learn how to create your own go to
+// https://hardhat.org/guides/create-task.html
+task("accounts", "Prints the list of accounts", async (taskArgs, hre) => {
+  const accounts = await hre.ethers.getSigners();
+
+  for (const account of accounts) {
+    console.log(account.address);
+  }
+});
+
+// You need to export an object to set up your config
+// Go to https://hardhat.org/config/ to learn more
+
+/**
+ * @type import('hardhat/config').HardhatUserConfig
+ */
+module.exports = {
+  solidity: "0.8.4",
+  networks: {
+    l1: {
+         url: process.env.L1URL,
+         accounts: [ process.env.PRIV_KEY ]
+    }
+  }
+};