Fix bug in Blob Manager, Cleanup Timer was not cancelled on Shutdown                                          -

The java8 Xdoclint:none fix was not correctly transferred when moving
the javadoc building to a jekyll plugin.

Also fixes a bug with Java/Scala interop: TupleTypeComparator was only checking
for nested Java Tuples and Pojos, not Scala Case classes.

This closes #146

Added Flink logo to JobManager web interface.
Updated Run Example Quickstart screenshots
Removed old gradients and unused image files from submission client.

This closes #145.

This closes #131

Added test cases.
Minor improvements and clean-ups.

[FLINK-1076] Extend Hadoop compatibility. Added wrappers for stand-alone Map, Reduce, and CombinableReduce functions.

This reverts commit 74dded1c.

Tests and documentation included. Also tested on cluster.

I hijacked @twalthr's PR #131 to build the documentation of the Hadoop function wrappers on top.

Author: Fabian Hueske <fhueske@apache.org>
Author: Artem Tsikiridis <artem.tsikiridis@cern.ch>
Author: twalthr <info@twalthr.com>

Closes #143 from fhueske/hadoopFunctions and squashes the following commits:

f1b3f21 [Fabian Hueske] [FLINK-1076] Extended Hadoop Compatibility documentation to cover Hadoop functions
f4be4a0 [twalthr] [FLINK-1107] Hadoop Compatibility Layer documented
4a62bdb [Fabian Hueske] [FLINK-1076] Return type determined via type extraction. Added test cases. Minor improvements and clean-ups.
df947d9 [Artem Tsikiridis] [FLINK-1076] Extend Hadoop compatibility. Added wrappers for stand-alone Map, Reduce, and CombinableReduce functions.

This also adds more integration tests, but not all tests of the Java API
have been ported to Scala yet.

- improved error messages
- the composite vs atomic bug aljoscha found
- Comparator test for Pojo Comparator enabled
- TODO removed
- string-based key expression for group sorting fields definition
- support for specifying "select all" using * and now also _ (for scala fans)
- Exception if user is having multiple fields with the same name in the class

This closes #136

Looped through the user code class loader from the envrionment to the tasks.

Added timed cleanup task to LibraryCacheManager to remove automatically unreferenced jar files. Moved registration logic out of the IOReadableWritable serialization logic. Updated logger.

Made the LibraryCacheManager an object instead of a Singleton.

Added proper shutdown of task manager and job manager.

Removed nio import to support Java 6 compilation.

Removed lock map from BlobLibraryCacheManager. Using global lock for synchronization. Marked StackOverflow code. Removed JavaDocs copyright message. Added getUserCodeClassLoader to AbstractInvokable class.

This closes #126 and closes #107.

Conflicts:
	flink-addons/flink-streaming/flink-streaming-connectors/pom.xml

[streaming] Connectors POM formatting fix

This closes #138