change contract name && fix addLiquidity

contracts/SmartRoute/DODOApprove.sol

@@ -0,0 +1,35 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+
+import {IERC20} from "../intf/IERC20.sol";
+import {SafeERC20} from "../lib/SafeERC20.sol";
+import {Ownable} from "../lib/Ownable.sol";
+
+contract DODOApprove is Ownable {
+    using SafeERC20 for IERC20;
+    address public dodoProxy;
+
+    function setDODOProxy(address _dodoProxy) external onlyOwner {
+        dodoProxy = _dodoProxy;
+    }
+
+    function getDODOProxy() public view returns (address) {
+        return dodoProxy;
+    }
+
+    function claimTokens(
+        address token,
+        address who,
+        address dest,
+        uint256 amount
+    ) external {
+        require(msg.sender == dodoProxy, 'DODOApprove:Access restricted');
+        IERC20(token).safeTransferFrom(who, dest, amount);
+    }
+}