Remove LibAssetProxyIds and TestLibConstants

contracts/asset-proxy/contracts/src/libs/LibAssetProxyIds.sol

@@ -1,40 +0,0 @@
-/*
-
-  Copyright 2019 ZeroEx Intl.
-
-  Licensed under the Apache License, Version 2.0 (the "License");
-  you may not use this file except in compliance with the License.
-  You may obtain a copy of the License at
-
-    http://www.apache.org/licenses/LICENSE-2.0
-
-  Unless required by applicable law or agreed to in writing, software
-  distributed under the License is distributed on an "AS IS" BASIS,
-  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-  See the License for the specific language governing permissions and
-  limitations under the License.
-
-*/
-
-pragma solidity ^0.5.5;
-
-
-contract LibAssetProxyIds {
-
-    // AssetProxy Ids are equiavalent the first 4 bytes of the keccak256 hash of the function signature assigned to each AssetProxy.
-
-    // ERC20Token(address)
-    bytes4 constant public ERC20_PROXY_ID = 0xf47261b0;
-
-    // ERC721Token(address,uint256)
-    bytes4 constant public ERC721_PROXY_ID = 0x02571792;
-
-    // ERC1155Assets(address,uint256[],uint256[],bytes)
-    bytes4 constant public ERC1155_PROXY_ID = 0xa7cb5fb7;
-
-    // MultiAsset(uint256[],bytes[])
-    bytes4 constant public MULTI_ASSET_PROXY_ID = 0x94cfcdd7;
-
-    // StaticCall(address,bytes,bytes32)
-    bytes4 constant public STATIC_CALL_PROXY_ID = 0xc339d10a;
-}