Implement to show version.
Prepare test environment with rspec.
Add test for Wloger::VERSION.
Refactoring to rename Wloger::Editor to Wloger::LogFile.
Change saved directory format.
Merge branch 'develop' into rspec

Conflicts:
	lib/wloger/command.rb
Add test for Wloger::Directory.
Merge branch 'readme' into develop
Fix bug not to call Wloger::Directory.remove_today.
Merge branch 'rspec' into develop
Fix unexpected change of attribute.
Improve test of #make_today & #remove_toda for Wloger::Directory.
Tweak.
Refactoring Wloger::LogFile & Wloger::Direcotry.
Update to version 0.0.4.

This update is minor update.
Merge branch 'develop'