[FLINK-1142] Log information about I/O manager temp dirs

This closes #219.
Minor code clean up

This closes #221.
[FLINK-1252] Add support for serializing Date and Enums in the Java API
[FLINK-1251] Enums are now handled properly by the collection input format
[FLINK-1252] address pull request comments

This closes #215
Added binary input and output format which uses the objects' TypeSerializer to serialize them.

Added InputTypeConfigurable to TypeSerializerOutputFormat to support a more seamless integration.

This closes #218.
[FLINK-1265] Fix user classloader bug for registerInputOutput() method
[Flink-1262] inconsistency between CsvReader.java and TupleGenerator.java

This closes #222
[FLINK-1264] [compiler] Properly forward custom partitioners to the runtime
[FLINK-820] [compiler] Support for disconnected data flows
Removed object reusage in GenericArraySerializer's deserialize method.
Log memory usage stats at INFO level instead of DEBUG
[APIs] Enhance test coverage for CollectionInputFormat and add tests for failed serializations of user code objects
[FLINK-1263] [optimizer] Implement compatibility checks for binary operators and custom partitioning

This closes #223
[streaming] Introduced a new invokable to allow flexible windowing based on trigger and eviction policies. Additionally created all required policy interfaces.
[streaming] Added interface for policy helpers. Such helpers will allow to use policy based windowing through a simpler API.
[streaming] Created trigger and eviction policies based on element counters. Included respective policy helper and test cases.
[streaming] Introduced extractor interface to enable flexible handling of arbitrary input data types.
[streaming] Created active trigger and eviction policies based on time. Included respective policy helper and test cases.
[streaming] Added extractor implementations for various extractions and conversions. (incl. test cases)