adding arrays_are_equal, uniquify, object_array_to_map, truthy_string and falsey_string
added tests for arrays_are_equal, uniquify, object_array_to_map, truthy_string and falsey_string
added arrays_are_equal, uniquify, object_array_to_map, truthy_string and falsey_string; sorted method list
bump version number to 0.4.0, in preparation for a release
added relese notes for v0.4.0