ADD: added two new learning methods and a new learning method able to cycle through user defined sequence of learning methods

ADD+MOD+FIX: added new evaluation functions for debug/testing purposes, modified random generation of parameters, fixed the calculation of gradient via backpropagation

ADD+MOD: added two new learning methods and a new learning method able to cycle through user defined sequence of learning methods

Every learning method now inherits from the abstract class LearningMethod, instead from the interface ILearningMethod.