Bug Fix / Bug 修正

* fixed : not having a unified unit of time, caused browser side heartbeat timeout. see `web-server/public/js/lib/build/build.js` for detail. [Link](https://github.com/ETiV/chatofpomelo-websocket/blob/master/web-server/public/js/lib/build/build.js#L1655).

The reason is that when the server side response the handshake. It tell heartbeat to browser side in unit of Second. But browser side consider this value as milliseconds. [Link](https://github.com/NetEase/pomelo/blob/master/lib/connectors/commands/handshake.js#L77)

* modified : package.json to update the version of dependent packages.

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* 由时间单位不统一而引起的浏览器端报心跳超时错误. 详见 `web-server/public/js/lib/build/build.js` [点击查看](https://github.com/ETiV/chatofpomelo-websocket/blob/master/web-server/public/js/lib/build/build.js#L1655)

这个错误是由于 `pomelo/lib/connectors/commands/handshake.js` 中，服务器作出`response`时，`heartbeat` 的取值用了 `heartbeatSec`。而在客户端，将其理解为毫秒单位所致。[点此查看](https://github.com/NetEase/pomelo/blob/master/lib/connectors/commands/handshake.js#L77)

* 修改了 package.json, 以更新依赖包的版本.

#### By The Way
同时提醒一下，有一处拼写错误, 在 `pomelo` 主代码中, `pomelo/lib/connectors/commands/heartbeat.js` Line 12 [Link](https://github.com/NetEase/pomelo/blob/master/lib/connectors/commands/heartbeat.js#L12):

    this.hearbeat = null;

拼写错误. 应为:

    this.heartbeat = null;

0.3.4 拼错了, MASTER 也拼错了. 搜索的话，还可以发现几处注释里也有错误的 `hearbeat`。