Author Name Disambiguation, Document Classification, etc.

Pig Scripts 
* the version of guava has changed after CDH upgrade

Document classification 
* rearrangement of (single) "document-classification" project to (parent) "document-classification" containing (workflow) "dc-classification-workflow", (workflow) "dc-model-building-workflow" and (jar+pig) "dc-logic"
* additional oozie-maven-plugin descriptors for selecting pig scripts according to needs of a given (workflow) project

Author Name Disambiguation:
* reimplanting Java exhaustive disambiguation (mainly Reducer Code) to exhaustiveAND Apache Pig UDF class (ExhaustiveAND), and extractor classes
* optimalizations for Exhaustive AND
* implementation of (optimalized) ApproximateAND
* Pig scrpit: new_disambiguation.pig
* a lot of smart work