In this Release Notes document, you will find the new features, enhancements and fixes of the Hazelcast Jet release. 
The numbers in the square brackets refer to the issue number in Hazelcast Jet GitHub repository. You can reach to the full descriptions of the issues at https://github.com/hazelcast/hazelcast-jet/issues/<issue number>.
The label in the brackets refer to the respective module.

** Hazelcast Jet 0.3.1 **

1. New features
- [core] The Jet cluster can be scaled up without affecting running jobs. Please refer to the [elasticity](https://github.com/hazelcast/hazelcast-jet-reference-manual/blob/master/src/Introduction.md#elasticity) section in the user guide for details. 

2. Enhancements

- [core] Improved DAG.toString [310] 
- [core] Convenience to make any processor non-cooperative [321] 
- [core] Update Hazelcast version to 3.8 [323] 
- [core] Add missing functional interfaces to the Distributed class [324] 
- [java.util.stream] Refactor of Jet collectors into a new type called Reducer [313]
- [java.util.stream] Allow branching of the j.u.s pipeline [318]
- [hadoop] Added support for reading and writing non-text data from or to HDFS. Please refer to the  [hazelcast-jet-hadoop documentation](https://github.com/hazelcast/hazelcast-jet-reference-manual/blob/master/src/Modules.md#hazelcast-jet-hadoop) for details.
- [hadoop] Added key/value mappers for ReadHdfsP and WriteHdfsP [328]
- [kafka] Kafka connector now makes use consumer groups. Please refer to (hazelcast-jet-kafka documentation) [https://github.com/hazelcast/hazelcast-jet-reference-manual/blob/master/src/Modules.md#hazelcast-jet-kafka] 
- [code-samples] Jet vs java.util.stream benchmark added to code samples
- [code-samples] New hadoop word count example added
- [code-samples] Kafka consumer example added

3. Fixes
- [core] Remove dead and potentially racy code from async operations [320] 
- [core] ReadSocketTextStreamP should emit items immediately after reading [335]
- [core] Wrong configuration file is used for IMDG when Jet config file present in classpath [345]
- [java.util.stream] Do not require forEach action to be serializable [340, 341] 
