Change file name of example subliem-settings.
Changed HatenaDo class.

If user account settings file is not correct format or not exist,
we don't allow HatenaPost and HatenaNewArticle command.
Add process to make account settings file.
#3 is over
 #4 is over.
#5 is over
delete TODO comment
moved settings_path inside is_settings_exist() method
 #6 is over
protect from json load empty file error
何度もrequestを投げない様にした
アカウントの初期設定時何度もリクエストを送っていたのを修正
README更新