0.4.0

Features:

• Implemented callbacks module to stop the optimization process based in the current iteration metrics, currently implemented:
  sklearn_genetic.callbacks.ThresholdStopping , sklearn_genetic.callbacks.ConsecutiveStopping and sklearn_genetic.callbacks.DeltaThreshold.
• The algorithms 'eaSimple', 'eaMuPlusLambda', 'eaMuCommaLambda' are now implemented in the module sklearn_genetic.algorithms
  for more control over their options, rather that taking the deap.algorithms module.
• Implemented the sklearn_genetic.plots module and added the function sklearn_genetic.plots.plot_search_space,
  this function plots a mixed counter, scatter and histogram plots over all the fitted hyperparameters and their cross-validation score.
• Documentation based in rst with Sphinx to host in read the docs. It includes public classes and functions documentation as well
  as several tutorials on how to use the package, link: https://sklearn-genetic-opt.readthedocs.io/
• Added best_params_ and best_estimator_ properties after fitting GASearchCV.
• Added optional parameters refit, pre_dispatch and error_score.

API Changes:

• Removed support for python 3.6, changed the libraries supported versions to be the same as scikit-learn current version.
• Several internal changes on the documentation and variables naming style to be compatible with Sphinx.
• Removed the parameters continuous_parameters, categorical_parameters and integer_parameters in GASearchCV, replacing them with param_grid.