[scala] Add withParameters() support for sinks/sources

This closes #261.
[FLINK-1310] Change ClosureCleaner Logging to DEBUG

This closes #262.
Enable flink-hbase module for hadoop1 build as well.

This commit is based on a diff by @fpompermaier (see https://github.com/apache/incubator-flink/pull/220).

This closes #220
[FLINK-1302] Make JDBCInputFormat implement the NonParallelInput interface
[FLINK-998] Close TCP connections after destroying logical channels

- 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.
Exclude docs/_site/** from License Check
[FLINK-1287] LocalizableSplitAssigner prefers splits with less degrees of freedom

This closes #258
[FLINK-1208] Enable CsvInputFormats to ignore invalid lines and lines starting with comments

This closes #201
[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.
Fixes broken code highlighting in documentation
[FLINK-1327] [core] Fix wrapping of MemorySegments in ByteBuffers