Java 8 support for streaming

The pull request contains the following:

1. Serialization rework for streaming for lambda expression support
1. A java 8 example for streaming placed in the flink-java8 project (it was not reasonable to either change the jre for flink-streaming-examples or to open a new flink-streaming-java8-examples project)
1. Some update on the flink-java8 project if I was already there
1. Lambda expression support for the output selector which is a functionality specific to streaming