Move 0x.js temnplates to 0x.js instead of having them as a separate package

packages/0x.js/contract_templates/contract.mustache

@@ -0,0 +1,25 @@
+/**
+ * This file is auto-generated using abi-gen. Don't edit directly.
+ * Templates can be found at https://github.com/0xProject/0x.js/tree/development/packages/abi-gen-templates.
+ */
+import {TxData, TxDataPayable} from '@0xproject/types';
+import {classUtils, promisify} from '@0xproject/utils';
+import {BigNumber} from 'bignumber.js';
+import * as Web3 from 'web3';
+
+import {BaseContract} from './base_contract';
+
+export class {{contractName}}Contract extends BaseContract {
+{{#each methods}}
+    {{#this.constant}}
+    {{> call contractName=../contractName}}
+    {{/this.constant}}
+    {{^this.constant}}
+    {{> tx contractName=../contractName}}
+    {{/this.constant}}
+{{/each}}
+    constructor(web3ContractInstance: Web3.ContractInstance, defaults: Partial<TxData>) {
+        super(web3ContractInstance, defaults);
+        classUtils.bindAll(this, ['web3ContractInstance', 'defaults']);
+    }
+} // tslint:disable:max-file-line-count