Renamed NepheleMiniCluster to FlinkMiniCluster.

Changed RuntimeEnvironment and TaskInputSplitProvider to work with ActorRefs.

Replacing the EventCollector and the MemoryArchivist.

Finished EventCollector and adjusted ExecutionGraph and ExecutionVertex to register actors as listeners.

added further communication logic to jobmanager and taskmanager.

Fixes race condition in ExecutionGraph which allowed a job to go into the finished state without all job vertices having properly processed the finalizeOnMaster method.

This closes #271

The performance of data-intensive jobs using Kryo is probably going to be slow.

Set correct classloader

try to use Kryo.copy() with fallback to serialization copy

This closes #273

The current examples show-case the API, more meaningful examples are coming for the 0.9 release.

PrintSinkFunction now explicitly states threads in output
Added printToErr functionality

This closes #269

Conflicts:
	flink-addons/flink-streaming/flink-streaming-core/src/main/java/org/apache/flink/streaming/api/environment/StreamExecutionEnvironment.java

Conflicts:
	flink-addons/flink-streaming/flink-streaming-core/src/main/java/org/apache/flink/streaming/api/JobGraphBuilder.java
	flink-addons/flink-streaming/flink-streaming-core/src/main/java/org/apache/flink/streaming/api/environment/StreamExecutionEnvironment.java

This closes #260

This closes #252

This closes #263

This closes #266

This closes #201

This closes #258

- This commit introduces reference-counting to keep track of the
  InputChannel and OutputChannel instances, which share the same
  physical TCP connection.

- When the logical channels are released, the reference count will
  reach 0 and the respective TCP connection can safely be closed.

- Furthermore, the debug thread in the OutboundConnectionQueue is
  properly shut down and all queued buffers are freed when the
  channel is closed or an Exception occurs.

This closes #255.