Fixed issue #46 for NeuralNetwork: remove the learningRateDiv parameter
Added documentation for the stochastic gradient parameters in NeuralNetwork
Previous fix to #46 was wrong (didn't pass the unit test). This one is good.
Minor changes and commenting relative to learning rate.
Fixed e-decreasing greedy policy epsilon value (issue #46).
Finally decided to use access methods instead of "read-only" members for current learningRate / epsilon.