Retire a deprecated recipe, and an even older alias.

Each component is now expected to install the version of ruby that it requires.
Rename an attribute to be more generic; keep the old one around for
a bit longer.
Since we are making a breaking change that will require updating and testing most if not all cookbooks, use it as an opportunity to bump ruby version to something up to date.
Release 1.3.0: improved support for running each component with a
different version of ruby.