getaddrinfo resolver throws away error code

[weissi]

NIO's default GAI resolver just throws away the error code and says unknown(host:port:). That's not quite right, lots of reasons why GAI could fail, NIO should provide that info to the user

[weissi]

See errors in https://www.man7.org/linux/man-pages/man3/getaddrinfo.3.html

[rnro]

Thanks for filing the issue - this makes sense, we should do it.