Offer buffer-oriented API for I/O and replace custom Java NIO TCP/IP code with Netty 4 library

This PR includes an old PR ((#511 | FLINK-511)), which has not been merged and replaces the custom Java NIO TCP/IP code with the Netty 4 library on top of it. See (#511 | FLINK-511) and (#25 | FLINK-25) for some notes on the buffer-oriented API.

Netty replaces our custom NIO code, which was used to setup the TCP connections and queue network envelopes. The main Netty-related stuff is located in the `runtime.io.network.netty` package: `NettyConnectionManager` and `OutboundConnectionQueue` are the entry points for connection setup and envelope queueing. `OutboundEnvelopeEncoder` and `InboundEnvelopeDecoder` take care of serialization and deserialization. All main components have respective test cases. I also went over the buffer-orientation changes but did not add any further tests since the original PR yet.

I will now run the test job on a cluster and get back to confirm that this also fixes (#652 | FLINK-652).

---------------- Imported from GitHub ----------------
Url: https://github.com/stratosphere/stratosphere/pull/892
Created by: uce
Labels:
Created at: Sun Jun 01 16:43:15 CEST 2014
State: closed