Gemfile in rbnacl-3.1.2 vs Gemfile in rbnacl-3.2.0

@@ -1,12 +1,17 @@
-source 'https://rubygems.org'
+source "https://rubygems.org"
 
 # Specify your gem's dependencies in rbnacl.gemspec
 gemspec
 
 group :development do
-  gem 'guard-rspec'
+  gem "guard-rspec"
 end
 
 group :test do
-  gem 'coveralls', :require => false
+  gem "coveralls", require: false
+  gem "rbnacl-libsodium"
+end
+
+group :development, :test do
+  gem "rubocop"
 end