🛁 Use XC-20 standard for contracts-watr TrueUSD (#1252)

packages/contracts-watr/.env.deploy.example

@@ -0,0 +1 @@
+TRUE_USD_ASSET_ID=1983

packages/contracts-watr/.env.test.example

@@ -0,0 +1,2 @@
+# required to run `yarn verify:deployments`
+PRIVATE_KEY_DEPLOYER=private_key

packages/contracts-watr/.gitignore

@@ -2,3 +2,6 @@
 /build
 /cache
 /flattened_contracts
+deployments-watr_local.json
+.env.test
+.env.deploy

packages/contracts-watr/contracts/TokenControllerV3.sol

@@ -85,7 +85,7 @@ contract TokenControllerV3 {
 
     // paused version of TrueCurrency in Production
     // pausing the contract upgrades the proxy to this implementation
-    address public constant PAUSED_IMPLEMENTATION = 0x3c8984DCE8f68FCDEEEafD9E0eca3598562eD291;
+    address public pausedImplementation;
 
     modifier onlyMintKeyOrOwner() {
         require(msg.sender == mintKey || msg.sender == owner, "must be mintKey or owner");
@@ -184,10 +184,11 @@ contract TokenControllerV3 {
         _;
     }
 
-    function initialize() external {
+    function initialize(address _pausedImplementation) external {
         require(!initialized, "already initialized");
-        owner = msg.sender;
         initialized = true;
+        pausedImplementation = _pausedImplementation;
+        owner = msg.sender;
     }
 
     /**
@@ -592,7 +593,7 @@ contract TokenControllerV3 {
      * @dev pause all pausable actions on TrueCurrency, mints/burn/transfer/approve
      */
     function pauseToken() external virtual onlyOwner {
-        IOwnedUpgradeabilityProxy(address(token)).upgradeTo(PAUSED_IMPLEMENTATION);
+        IOwnedUpgradeabilityProxy(address(token)).upgradeTo(pausedImplementation);
     }
 
     /**

packages/contracts-watr/contracts/TrueCurrency.sol

@@ -2,6 +2,7 @@
 pragma solidity 0.6.10;
 
 import {BurnableTokenWithBounds} from "./common/BurnableTokenWithBounds.sol";
+import {SafeMath} from "@openzeppelin/contracts/math/SafeMath.sol";
 
 /**
  * @title TrueCurrency
@@ -39,6 +40,8 @@ import {BurnableTokenWithBounds} from "./common/BurnableTokenWithBounds.sol";
  * - ERC20 Tokens and Ether sent to this contract can be reclaimed by the owner
  */
 abstract contract TrueCurrency is BurnableTokenWithBounds {
+    using SafeMath for uint256;
+
     uint256 constant CENT = 10**16;
     uint256 constant REDEMPTION_ADDRESS_COUNT = 0x100000;
 
@@ -54,10 +57,11 @@ abstract contract TrueCurrency is BurnableTokenWithBounds {
      */
     event Mint(address indexed to, uint256 value);
 
-    function initialize() external {
+    function initialize(address _nativeToken) external {
         require(!initialized, "already initialized");
-        owner = msg.sender;
         initialized = true;
+        owner = msg.sender;
+        nativeToken = _nativeToken;
     }
 
     /**
@@ -126,8 +130,9 @@ abstract contract TrueCurrency is BurnableTokenWithBounds {
         require(!isBlacklisted[recipient], "TrueCurrency: recipient is blacklisted");
 
         if (isRedemptionAddress(recipient)) {
-            super._transfer(sender, recipient, amount.sub(amount.mod(CENT)));
-            _burn(recipient, amount.sub(amount.mod(CENT)));
+            uint256 _amount = amount.sub(amount.mod(CENT));
+            super._transfer(sender, recipient, _amount);
+            _burn(recipient, _amount);
         } else {
             super._transfer(sender, recipient, amount);
         }

packages/contracts-watr/contracts/common/ProxyStorage.sol

@@ -61,6 +61,9 @@ contract ProxyStorage {
     address public chainReserveFeed;
     bool public proofOfReserveEnabled;
 
+    // XC20Wrapper variables
+    address public nativeToken;
+
     /* Additionally, we have several keccak-based storage locations.
      * If you add more keccak-based storage mappings, such as mappings, you must document them here.
      * If the length of the keccak input is the same as an existing mapping, it is possible there could be a preimage collision.

packages/contracts-watr/contracts/common/ReclaimerToken.sol

@@ -3,14 +3,14 @@ pragma solidity 0.6.10;
 
 import {IERC20} from "@openzeppelin/contracts/token/ERC20/IERC20.sol";
 import {ITrueCurrency} from "../interface/ITrueCurrency.sol";
-import {ERC20} from "./ERC20.sol";
+import {XC20Wrapper} from "./XC20Wrapper.sol";
 
 /**
  * @title ReclaimerToken
  * @dev ERC20 token which allows owner to reclaim ERC20 tokens
  * or ether sent to this contract
  */
-abstract contract ReclaimerToken is ERC20, ITrueCurrency {
+abstract contract ReclaimerToken is XC20Wrapper, ITrueCurrency {
     /**
      * @dev send all eth balance in the contract to another address
      * @param _to address to send eth balance to