getters-setters.

* src/core/java/com/dataiku/dip/datalayer/streamimpl/StreamContext.java:
  Here.
style: Indent.

* src/core/java/com/dataiku/dip/datalayer/SingleRowProcessor.java: Here
getters-setters.

* src/core/java/com/dataiku/dip/datalayer/SingleRowProcessor.java,
  src/core/java/com/dataiku/dip/input/filter/InputSampler.java:
  Here.
Use StringBuilder

* src/core/java/com/dataiku/dip/partitioning/Partition.java: Here.
clone -> implements Cloneable.

* src/core/java/com/dataiku/dip/partitioning/Partition.java: Here.