Merge pull request #377 from tiagoantao/master

a few more issues
Merge pull request #378 from tiagoantao/master

A couple more divs...
Adjusted NonreducedFraction docstring.
Wrote MenuSection and MenuEntry format tests.
Alphabetized MenuEntry initializer keywords.
Alphabetized MenuSection initializer keywords.
Removed Menu initializer keyword.

Remove include_default_menu_sections=False keyword from Menu initializer.

Use Menu._make_default_menu_sections() instead.
Alphabetized Menu initializer keywords.
Wrote UserInputGetterPrompt format tests.
Subclassed ScorePackageWrangler._make_asset_menu_entries().

Score packages are listed with diacritics and year of completion.
Extended MenuSection._argument_range_string_to_numbers().

The method now knows how to detect argument_range_string input that is not
in fact an argument range. This is helpful because the method can then treat
the argument_range_string input as a sigle string against which to match.

This commit also extend Menu._argument_range_string_to_numbers() to match
against argument_range_string input in a case-neutral way. This means that ...

    Red Example Score
    RED EXAMPLE SCORE
    red example score
    rEd eXAMplE scOrE

... will all match and return the index of the score in the target menu
section.
Wrote ScorePackageManager.remove_score_package() tests.
Wrote more ScorePackageManager.remove_score_package() tests.
Extended MenuSection._argument_range_string_to_numbers().

The method now handles ranges like ...

    "Test Score 100 - Test Score 101"

... correctly.

This is made possible by stripping whitespace at the right times.
Made Wrangler._get_available_path() private.

Method doesn't need to be documented in API.
Removed metadata management methods from Wrangler.

MODEL: metadata belong to a directory.
Updated TODO.
Wrote ScorePackageWrangler.doctest() test.
Removed redundant command section from main menu.

The 'library' section repeated the commands of the 'go' section exactly.
Updated TODO.