Netty: Support to bind on multiple host/port pair

This PR allows to bind to more than host and port using the `bind_host` and `port` properties. You can basically create differrent profiles, which can also have different tcp and buffer settings.

TODO: Documentation, explain possible options
nullifying the serverChannel is meaningless now I think, so no need for the final clause. Can we open an iterator, and use it to *remove* the relevant channel, and wrap the close method in a try catch blog with debug log on failures for each channel?