Normalize the dependencies

packages/contracts/util/order.ts

@@ -1,16 +1,11 @@
-import { BigNumber, promisify } from '@0xproject/utils';
+import { BigNumber } from '@0xproject/utils';
 import { Web3Wrapper } from '@0xproject/web3-wrapper';
 import ethUtil = require('ethereumjs-util');
 import * as _ from 'lodash';
-import Web3 = require('web3');
 
 import { crypto } from './crypto';
 import { OrderParams } from './types';
 
-// In order to benefit from type-safety, we re-assign the global web3 instance injected by Truffle
-// with type `any` to a variable of type `Web3`.
-const web3: Web3 = (global as any).web3;
-
 export class Order {
     public params: OrderParams;
     private _web3Wrapper: Web3Wrapper;