Add scaffold for evaluation functions.
Add some error measures.
Add CE implementation.
Add scaffold for evaluation functions.

Conflicts:

	test/test.cpp
Add some error measures.
Add CE implementation.
add prototypes for crossValidation and add some forward declaration.
implement crossValidation in Evaluation.cpp
add classificationHits(Learner&, DataSet&) to OpenANN's interface.
Merge branch 'evaluation' of https://github.com/Ruun/OpenANN into Ruun-evaluation

Conflicts:
	OpenANN/Evaluation.h
	src/Evaluation.cpp
	test/EvaluationTestCase.cpp
	test/test.cpp
Test cross entropy.
Simplify tests.
Add accuracy and confusion matrix.
Document evaluation functions.
Merge branch 'evaluation'
Remove doxygen warning.