Attempt to duplicate the functionality of Rails' old class_inheritable_ary
without monkey-patching base-classes or polluting target classes with
unexpected methods/attributes

Basic use-case:
gem install class_inheritable
irb
require 'class_inheritable'
class MyClass
ClassInheritable::Array.attach :to => self, :as => :foo
append_foo :bar
end
class MySubClass < MyClass
append_foo :baz
end

[:bar] == MyClass.foo
[:bar] == MyClass.new.foo

[:bar, :baz] == MySubClass.foo
[:bar, :baz] == MySubClass.new.foo

(See specs for more detailed use-cases.)
rspec ./spec/lib/class_inheritable/array_spec.rb