Updating ruby to azukiapp/node image

[azukiapp/ruby:2.1](https://registry.hub.docker.com/u/azukiapp/ruby/)
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Base docker image to run Ruby applications

- Git
- Ruby 2.1.2
- RubyGems 2.3.0
- NodeJS
- Bundler
- MySQL Client
- PostgreSQL Client
- MongoDB
- ImageMagick

[azuki/ruby:1.9](https://registry.hub.docker.com/u/azukiapp/ruby/)
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Base docker image to run Ruby applications

- Git
- Ruby 1.9.3-p551
- RubyGems 2.3.0
- Bundler
- NodeJS
- MySQL Client
- PostgreSQL Client
- MongoDB
- ImageMagick