mruby/mruby — pull request #512 by tsahara-iij (2012-10-29 02:18:08+00:00)
Title: IO.printf returns nil on CRuby

Just for better compatibility with CRuby:

```
% ruby -e 'p $stdout.printf "a\n"'
a
nil

% mruby -e 'p $stdout.printf "a\n"'
a
"a\n"
```