Documents style
Clarify to use ASCII-8bit for Ruby2.0+
Split versioning file
Documents
Update examples
Refactor
Fix feature of `deprecteds` that prints warnings when parsing

* With refactoring
* Add some reflections

Fix #6
Add versioning test
Simplify OptArg.members
Rename debugging API `OptArg.names -> OptArg.names_with_autonym`
Bump version to 0.1.0