compiles socks5 in rustc 1.5.0-dev

[r-arias]

I had trouble compiling this with latest Rust (see #3), so I went ahead and fixed the errors the compiler was giving. Obviously I don't have any real idea what I am doing since this is not my code, and I am not particularly familiar with SOCKS. Nor am I an experienced Rust programmer yet ;)
I need SOCKS5 to work, so I focused on that for the last couple of hours. The same changes should be applicable to the other files but I am not sure I will get to it in the next couple of days.

As for the actual code changes, I was worried at one particular place, where I needed to replace a call to TcpStream::read_at_least(len, &mut buff) by TcpStream::read_exact(&mut buff). The former has been completely removed from std::io::Read, the latter is marked unstable. I am not sure about the semantics of read_at_least, so I am not sure my change leaves the semantics of the library intact. Would be nice if you could have a look!
Thanks,
R

[r-arias]

jsyk, I tested this and got a successful Tor connection through rustsocks + hyper :)

good night