ADD allTheSameOutput and allTheSame methods to the interface and implementations
CHANGE C4.5
Merge branch 'datasource_refactor' of github.com:kronenthaler/libai into datasource_refactor

Conflicts:
	src/libai/classifiers/refactor/DataSet.java
	src/libai/classifiers/refactor/TextFileDataSet.java
ADD Gain Information structure