refactor: move standards into toplevel folder

packages/contracts/contracts/L2/messaging/L2StandardBridge.sol

@@ -12,7 +12,7 @@ import { CrossDomainEnabled } from "../../libraries/bridge/CrossDomainEnabled.so
 import { Lib_PredeployAddresses } from "../../libraries/constants/Lib_PredeployAddresses.sol";
 
 /* Contract Imports */
-import { IL2StandardERC20 } from "../../libraries/standards/IL2StandardERC20.sol";
+import { IL2StandardERC20 } from "../../standards/IL2StandardERC20.sol";
 
 /**
  * @title L2StandardBridge

packages/contracts/contracts/L2/messaging/L2StandardTokenFactory.sol

@@ -2,7 +2,7 @@
 pragma solidity ^0.8.8;
 
 /* Contract Imports */
-import { L2StandardERC20 } from "../../libraries/standards/L2StandardERC20.sol";
+import { L2StandardERC20 } from "../../standards/L2StandardERC20.sol";
 import { Lib_PredeployAddresses } from "../../libraries/constants/Lib_PredeployAddresses.sol";
 
 /**

packages/contracts/contracts/L2/predeploys/OVM_ETH.sol

@@ -5,7 +5,7 @@ pragma solidity ^0.8.8;
 import { Lib_PredeployAddresses } from "../../libraries/constants/Lib_PredeployAddresses.sol";
 
 /* Contract Imports */
-import { L2StandardERC20 } from "../../libraries/standards/L2StandardERC20.sol";
+import { L2StandardERC20 } from "../../standards/L2StandardERC20.sol";
 
 /**
  * @title OVM_ETH

packages/contracts/contracts/libraries/standards/IWETH9.sol

-// SPDX-License-Identifier: GPL-2.0-or-later
-pragma solidity ^0.8.8;
-import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
-
-/// @title Interface for WETH9. Also contains the non-ERC20 events
-/// normally present in the WETH9 implementation.
-interface IWETH9 is IERC20 {
-    event Deposit(address indexed dst, uint256 wad);
-    event Withdrawal(address indexed src, uint256 wad);
-
-    /// @notice Deposit ether to get wrapped ether
-    function deposit() external payable;
-
-    /// @notice Withdraw wrapped ether to get ether
-    function withdraw(uint256) external;
-}

packages/contracts/contracts/libraries/standards/L2StandardERC20.sol → packages/contracts/contracts/standards/L2StandardERC20.sol

@@ -2,7 +2,6 @@
 pragma solidity ^0.8.8;
 
 import { ERC20 } from "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-
 import "./IL2StandardERC20.sol";
 
 contract L2StandardERC20 is IL2StandardERC20, ERC20 {