[FLINK-1324] [runtime] Trailing data is cached before the local input strategies are closed.
[FLINK-1322] Make Scala API respect WriteMode set in Config

This closes #266
[scala] Change ScalaAggregateOperator to use TypeSerializer

This closes #263
[misc] Fix/suppress various compiler warnings.
[FLINK-1305] [FLINK-1304] Test for HadoopInputWrapper and NullWritable support

This closes #252
[FLINK-1307] Allow file input from nested directory structure

This closes #260
[FLINK-1307] Excluded directories that match the file-filter from recursive descent.
deprecated current aggregation code
Test cases and API for new aggregations
ungrouped aggregations
grouped aggregations
missing license headers
moved AggregationUdf into correct package
name the aggregation operator in the DAG
additional tests for aggregation
CountAggregationFunction does not need an input type
documentation updates
fixed test case
fixed CI build
renamed old aggregation convenience functions