Gemfile in mojo_magick-0.5.7 vs Gemfile in mojo_magick-0.6.0

@@ -1,5 +1,10 @@
-source 'https://rubygems.org'
+source "https://rubygems.org"
+
+group :test, :development do
+  gem 'irb', require: false
+  gem 'simplecov', require: false
+end
 
 gemspec