接受到一个请求后， anyproxy报错，自动关闭

Plese fill the template when you reporting a new issue, thanks!

#### Which platform are you running AnyProxy

Mac
#### The version of the AnyProxy

4.0.12

#### Your expected behavior of AnyProxy

#### The actual behavior of AnyProxy

#### The log of the error

[AnyProxy Log][2018-10-11 16:09:10]: received request to: GET www.localnetwork.uop/
[AnyProxy ERROR][2018-10-11 16:09:10]: Error: getaddrinfo ENOTFOUND www.localnetwork.uop www.localnetwork.uop:80
[AnyProxy ERROR][2018-10-11 16:09:11]: got an uncaught exception, is there anything goes wrong in your rule file ?
Error: read ECONNRESET
at TCP.onStreamRead (internal/stream_base_commons.js:111:27)
[AnyProxy Log][2018-10-11 16:09:11]: destorying https connection : 127.0.0.1:62976
[AnyProxy Log][2018-10-11 16:09:11]: endding https cltSocket : 127.0.0.1:62976
[AnyProxy Log][2018-10-11 16:09:11]: clearing cache file...
[AnyProxy Log][2018-10-11 16:09:11]: ==>>> clearing cache
[AnyProxy Log][2018-10-11 16:09:11]: closing webserver...

Start by reproducing the failure on Mac with AnyProxy 4.0.12 using a request to the unresolved host shown in the log, then trace handling for the getaddrinfo ENOTFOUND and ECONNRESET errors. Done should be demonstrated by AnyProxy remaining available after the failed request instead of closing its webserver.

Written by the indexing model from the issue text.