Add ruby/Gemfile, ruby/Gemfile.lock
+ gem 'rspec'
Enabled to execute rspec
Defined redis client
Add spec/spec_helper.rb
Redis client flush all before each spec
post_article method creates article with 5 attributes
Use pry
Add ZSET having score key and ZSET having time key
Add .rspec
Add article_vote method
Get articles ordered by score
Get group articles
Remove all keys from the current database before each spec
Remove specs without spec similar to python version
Add README.md
Select db: 15
Merge pull request #8 from inouetakuya/add-ruby-sources

Ruby version samples for chapter 1