Move `Kernel#describe` to Spec::DSL
Remove `ARGV` stub
No need to double-define the inheritance
Initialize reporters with the same arguments
Move development dependencies to Gemfile
Add pry
Remove unnecessary `ensure`
Refactor `Runnable.runnables=`
Fix spelin
Refactor `Spec::Expect#to`
Keep requires in the top-level
Add anonymous it-descriptions

Why blank? They are blank after all
Make `Spec::DSL.create_sub_klass` private
Add Spec.name and Spec.to_s
Refactor - move sample tests to test/sample/tests
Extract teardown hooks to constant
Test spec verbosity for ProgressReporter