本服务器80端口全转发至AnyProxy代理的端口，访问80端口报错

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#### Which platform are you running AnyProxy

CentOS 6.5
#### The version of the AnyProxy

4.0 beta 13

#### Your expected behavior of AnyProxy

能够代理成功
#### The actual behavior of AnyProxy

不能正常代理
#### The log of the error

服务端日志：
[AnyProxy Log][2017-06-20 18:05:14]: received request to: GET init-p01st.push.apple.com/bag
[AnyProxy Log][2017-06-20 18:05:14]: received request to: GET init-p01st.push.apple.com/bag
[AnyProxy Log][2017-06-20 18:05:14]: received request to: GET init-p01st.push.apple.com/bag
[AnyProxy ERROR][2017-06-20 18:05:14]: Error: getaddrinfo ENOTFOUND localhost localhost:80

客户端日志：
# AnyProxy Inner Error
Oops! Error happend when AnyProxy handle the request.
This is an error occurred inside AnyProxy, not from your target website.
Error:
Error: connect EMFILE 127.0.0.1:80 - Local (undefined:undefined)
URL:
/
Error: connect EMFILE 127.0.0.1:80 - Local (undefined:undefined)
at Object.exports._errnoException (util.js:1016:11)
at exports._exceptionWithHostPort (util.js:1039:20)
at internalConnect (net.js:933:16)
at GetAddrInfoReqWrap.emitLookup [as callback] (net.js:1062:7)
at GetAddrInfoReqWrap.onlookup [as oncomplete] (dns.js:96:10)

Start with the server and client logs, then trace the Node.js stack entries at internalConnect and dns.js while reproducing the port-80 forwarding setup on CentOS 6.5 with AnyProxy 4.0 beta 13. Done means requests proxy successfully without the getaddrinfo or EMFILE errors.

Written by the indexing model from the issue text.