multi layer proxy example.

[ohaddahan]

In this configuration we have a public master server, which accepts
outgoing connections from endpoint servers.
The reason for using outgoing connections, is to avoid the need to open firewall ports.
The master will receive requests and forward them one of the servers connected to it.

(since it's in examples I merged it into one file/binary, in the real world the two servers are obviously not in the same process)

[ohaddahan]

@hatoo helped a lot in building this.

[seanmonstar]

I appreciate the interesting example! However, I'm trying to now limit how many examples are in the repository, since they increase compile/test time and maintenance. It would certainly be an interesting blog post, though!