add dvm && dpp admin control

contracts/DODOVendingMachine/intf/IDVM.sol

@@ -33,4 +33,21 @@ interface IDVM {
     function sellQuote(address to) external returns (uint256);
 
     function buyShares(address to) external returns (uint256);
+
+
+    //=========== admin ==========
+    function setLpFeeRateModel(address newLpFeeRateModel) external;
+
+    function setMtFeeRateModel(address newMtFeeRateModel) external;
+
+    function setTradePermissionManager(address newTradePermissionManager) external;
+
+    function setMaintainer(address newMaintainer) external;
+
+    function setGasPriceSource(address newGasPriceLimitSource) external;
+
+    function setBuy(bool open) external;
+
+    function setSell(bool open) external;
+   //============================== 
 }

contracts/DODOVendingMachine/intf/IDVMAdmin.sol

@@ -0,0 +1,13 @@
+/*
+
+    Copyright 2020 DODO ZOO.
+    SPDX-License-Identifier: Apache-2.0
+
+*/
+
+pragma solidity 0.6.9;
+pragma experimental ABIEncoderV2;
+
+interface IDVMAdmin {
+    function init(address owner, address _dvm) external;
+}