Add support for colouring test output

ruby/Gemfile

@@ -2,5 +2,6 @@ source 'https://rubygems.org'
 group :development, :test do
   gem 'guard'
   gem 'guard-minitest'
+  gem 'minitest-rg'
   gem 'rb-readline'
 end

ruby/Gemfile.lock

@@ -24,6 +24,8 @@ GEM
     lumberjack (1.0.13)
     method_source (0.9.2)
     minitest (5.11.3)
+    minitest-rg (5.2.0)
+      minitest (~> 5.0)
     nenv (0.3.0)
     notiffany (0.1.1)
       nenv (~> 0.1)
@@ -45,6 +47,7 @@ PLATFORMS
 DEPENDENCIES
   guard
   guard-minitest
+  minitest-rg
   rb-readline
 
 BUNDLED WITH

ruby/Guardfile

@@ -1,4 +1,4 @@
-guard :minitest, test_folders: '.', test_file_patterns: '*_test.rb' do
+guard :minitest, cli: '--rg', test_folders: '.', test_file_patterns: '*_test.rb' do
   watch(%r{^(.+)_test\.rb}) { |m| "./#{m[1]}_test.rb" }
   watch(%r{^(.+)\.rb}) { |m| "./#{m[1]}_test.rb" }
 end