The streaming code is in "flink-addons", for new/experimental code.
Documents should come over the next days/weeks, definitely before we make this part of the core. Right now, I would suggest to have a look at some of the examples, to get a feeling for the addon, check for example this here: https://github.com/apache/incubator-flink/tree/master/flink-addons/flink-streaming/flink-streaming-examples/src/main/java/org/apache/flink/streaming/examples/wordcount (The example reads a file for simplicity, but the project also provides connectors for Kafka, RabbitMQ, ...)
