Gemfile in citeproc-ruby-2.0.0 vs Gemfile in citeproc-ruby-2.1.0

@@ -6,27 +6,26 @@
 
 group :development, :test do
   gem 'rake'
   gem 'rspec'
   gem 'cucumber'
-  gem 'unicode_utils', require: false unless RUBY_VERSION >= '2.4'
 end
 
 group :debug do
-  gem 'byebug', :require => false, :platforms => :mri
-  gem 'ruby-debug', :require => false, :platforms => :jruby
+  gem 'debug', '>= 1.0.0', require: false, platforms: :mri
+  gem 'ruby-debug', require: false, platforms: :jruby
 end
 
 group :optional do
   gem 'edtf'
 	gem 'chronic'
 end
 
 group :extra do
-  gem 'pry'
 	gem 'yard', platforms: :mri
 	gem 'redcarpet', platforms: :mri
 end
 
 group :coverage do
   gem 'simplecov', require: false
+  gem 'simplecov-lcov', require: false
 end