[Feature request] Full support for proxy parameter

[burbilog]

I tried to compile this https://github.com/Genymobile/gnirehtet/pull/504 and it works, at least for me it's usable this way.

But I had to compile in my own proxy server ip. Proxy server setting should be passed from server command line with parameter like -P http://ip:3128 from server side.

Please, implement it, it's a great feature.