Add debugging dependencies

Author: russell-stripe

phabricator.gemspec

@@ -24,7 +24,10 @@ Gem::Specification.new do |spec|
   spec.add_development_dependency 'minitest', '< 5.0'
   spec.add_development_dependency 'minitest-reporters'
   spec.add_development_dependency 'mocha'
-  spec.add_development_dependency('rake')
+  spec.add_development_dependency 'rake'
+  spec.add_development_dependency 'byebug'
+  spec.add_development_dependency 'pry'
+  spec.add_development_dependency 'pry-byebug'
 
   spec.add_development_dependency 'bundler', '~> 1.3'
 end