移除getQRCode接口，补充单元测试

Author: JacksonTian

lib/common.js

@@ -256,23 +256,6 @@ API.prototype._removeMenu = function (callback) {
   urllib.request(url, {dataType: 'json'}, wrapper(callback));
 };
 
-/**
- * 获取二维码
- * @param {Object} data 二维码数据
- * @param {Function} callback 回调函数
- */
-API.prototype.getQRCode = function (data, callback) {
-  this.preRequest(this._getQRCode, arguments);
-};
-
-/*!
- * 获取二维码的未封装版本
- */
-API.prototype._getQRCode = function (data, callback) {
-  var url = this.prefix + 'qrcode/get?access_token=' + this.token.accessToken;
-  urllib.request(url, postJSON(data), wrapper(callback));
-};
-
 /**
  * 创建临时二维码
  * 详细请看：<http://mp.weixin.qq.com/wiki/index.php?title=生成带参数的二维码>
@@ -508,7 +491,7 @@ API.prototype._moveUserToGroup = function (openid, groupId, callback) {
   // https://api.weixin.qq.com/cgi-bin/groups/members/update?access_token=ACCESS_TOKEN
   // POST数据格式：json
   // POST数据例子：{"openid":"oDF3iYx0ro3_7jD4HFRDfrjdCM58","to_groupid":108}
-  var url = this.prefix + 'groups/update?access_token=' + this.token.accessToken;
+  var url = this.prefix + 'groups/members/update?access_token=' + this.token.accessToken;
   var data = {
     "openid": openid,
     "to_groupid": groupId
@@ -714,8 +697,8 @@ API.prototype.sendVoice = function (openid, mediaId, callback) {
 API.prototype._sendVoice = function (openid, mediaId, callback) {
   // {
   //  "touser":"OPENID",
-  //  "msgtype":"image",
-  //  "image": {
+  //  "msgtype":"voice",
+  //  "voice": {
   //    "media_id":"MEDIA_ID"
   //  }
   // }

package.json

@@ -34,6 +34,7 @@
     "supertest": "*",
     "mocha": "*",
     "should": "*",
+    "expect.js": "*",
     "connect": "*",
     "blanket": "*",
     "travis-cov": "*",