Some useful links to explain the concepts of Ruby
- https://stackoverflow.com/questions/15708916/use-rvmrc-or-ruby-version-file-to-set-a-project-gemset-with-rvm
- https://stackoverflow.com/questions/4667150/what-is-the-best-way-to-uninstall-gems-from-a-rails3-project
- https://dev.to/molly_struve/how-to-setup-a-readonly-rails-console-1j1a
- http://syndicode.co/2018/01/29/books-and-tutorials-for-learning-and-mastering-ruby-language
- https://stackoverflow.com/questions/14289217/im-getting-rvm-is-not-a-function-error-on-mac-os-x-and-no-posted-solutions-w
- https://www.exceptionalcreatures.com/bestiary/Net/OpenTimeout.html
- https://dev.to/exampro/testunit-writing-test-code-in-ruby-part-1-of-3-44m2
- http://engineering.pivotal.io/post/debugging-ruby-memory-issues-cloud-foundry-cloud-controller/