Merge branch 'hotfix/ruby-2.1.2' into develop
Merge branch 'hotfix/dummy' into develop
Merge branch 'hotfix/travis' into develop
Merge branch 'hotfix/codeforces' into develop
Merge branch 'hotfix/update-ruby' into develop
rubygems: Use google-api-client
Support AtCoder
AtCoder: support other contest
Merge branch 'hotfix/travis-fix' into develop
AtCoder: Change URL
fix spec
Merge branch 'hotfix/travis' into develop
fix url
disuse sinatra-contrib
use signing
disuse oauth
fix atcoder
disuse user credentials
disuse user_credentials
fix date