adding `label_separator` option, it's only enable when `labeled` option is true.
remove `separator` parameter not used
remove comment and rename `label_delimiter` to `label_separator`
Merge pull request #4 from suzuken/feature/change_label_separator

add `label_delimiter` option
0.3.4
Update README.md
Support --log option and default to STDOUT rather than STDERR
0.3.5