[TACHYON-62] Netty

Netty implementation of the data server.

This patch is not done yet.  Its intent is to show the work I have right now for commenting.

This PR should not be merged until performance results come in.
Are you talking about Netty socket channel options? For this patch I think OioServerSocketChannel is similar to the old NIO code which has different config option. 

The channel type hence only control nio or epoll.