Allow to use pry-byebug 3.8.0
Allow to use pry-byebug 3.8.0

`s.add_development_dependency 'pry-byebug', '~> 3.0.0'` locks pry-byebug
version to 3.0.1 (February 04, 2015) which is pretty old version.

thuehlinger/daemons