Add Enumerable#one?
Merge pull request #1926 from suzukaze/add-enum.one

Add Enumerable#one?
Enumerable#one? to prune iteration when count > 1; ref #1926
move conditional out of loop
Count crashed tests in total tests count.
Hash#__update fix typo
It's called by create Hash of over 126 keys
Merge pull request #1927 from take-cheeze/count_crash

Count crashed tests in total tests count.
remove unnecessary operator method call; ref #1927
Merge pull request #1928 from ksss/fix-typo

Hash#__update fix typo
Implement \u notation for strings and regexes.

This change adds the \u notation for double quoted strings and regular
expressions.  It does not implement the \u notation for character literals.
Both the \uNNNN and \u{NNNN} notations are supported.

\uNNNN is implemented by emitting equivalent UTF-8; that is, "\u4000" is
equivalent to "\xE4\x80\x80".

Unlike CRuby, the \u{NNNN} notation allows only one character per pair of
braces; I see no way to lift this restriction without remodeling the parser.
Small correction to the test identification.
Enumerable#each_with_object
fix multiple value handling; ref #1931
Merge pull request #1930 from chasonr/unicode-escape

Implement \u notation for strings and regexes.
Add Enumerable#reverse_each
Merge pull request #1932 from suzukaze/add-enum.reverse_each

Add Enumerable#reverse_each
improve Enumerable#reverse_each to be efficient