Release v0.2.10

• added logging_level parameter to the start method of the weka.core.jvm module, enabling the user to turn off debugging output in an easy way (#40)
• added method cv_splits to class Instances from module weka.core.dataset to return a list of train/test tuples as used by cross-validation
• the Tester class (module: weka.experiments) now has an option to swap columns/rows for comparing datasets rather than classifiers
• the SimpleExperiment class and derived classes (module: weka.experiments) now have the additional parameters in the constructor: class_for_ir_statistics, attribute_id, pred_target_column
• the method is_installed (module: weka.core.packages) now can check whether a specific version is installed
• added pww-packages entry point to allow managing of Weka packges from the command-line (actions: list/info/install/uninstall/suggest/is-installed)