Resolve "NaN in cv_results leads to exception"

Closes #49

See merge request !33

Resolve "print_gridsearch_results not suitable for multiple scores"

Closes #52

See merge request !32

Resolve "OSError in storage handler"

Closes #51

See merge request !31

Resolve "Random Classifer with uniform and data induced distribution"

Closes #50

See merge request !30

Resolve "Allow extraction of multiple metrics from gridsearch parameters"

Closes #48

See merge request !29