Added mavericks install guide
Merge branch 'develop' into feature/mavericks_installation_guide
Add links to chruby and ruby-install
Friendlier gcc success test
not yet at ruby 2.9
Merge pull request #15 from ralovely/hotfix/mavericks_installation_guide

Hotfix/mavericks installation guide
Merge pull request #14 from reinteractive-open/feature/mavericks_installation_guide

Feature/mavericks installation guide