major changes to random_layer.py - main class is RandomLayer,

and MLPRandomLayer and RBFRandomLayer are derived from it.
main classes in elm.py changed to GenELMRegressor and GenELMClassifier,
with ELMRegressor derived from GenELMRegressor, and ELMClassifier
derived from ELMRegressor
plot_elm_comparison.py and elm_notebook.py changed to follow API changes

Author: dclambert