sync Gemfile{,.lock} with main repo

Gemfile

@@ -2,7 +2,8 @@ source 'https://rubygems.org'
 
 group :test do
   gem 'rake'
-  gem 'minitest', '5.3'
+  gem 'minitest', '5.4.1'
   gem 'minitest-colorize'
-  gem 'mocha', '0.14.0', :require => false
+  gem 'mocha', '1.1.0', :require => false
+  gem 'rspec', '~> 3.0.0'
 end

Gemfile.lock

@@ -1,19 +1,33 @@
 GEM
   remote: https://rubygems.org/
   specs:
+    diff-lcs (1.2.5)
     metaclass (0.0.4)
-    minitest (5.3.0)
+    minitest (5.4.1)
     minitest-colorize (0.0.5)
       minitest (>= 2.0)
-    mocha (0.14.0)
+    mocha (1.1.0)
       metaclass (~> 0.0.1)
-    rake (10.3.2)
+    rake (10.0.4)
+    rspec (3.0.0)
+      rspec-core (~> 3.0.0)
+      rspec-expectations (~> 3.0.0)
+      rspec-mocks (~> 3.0.0)
+    rspec-core (3.0.2)
+      rspec-support (~> 3.0.0)
+    rspec-expectations (3.0.2)
+      diff-lcs (>= 1.2.0, < 2.0)
+      rspec-support (~> 3.0.0)
+    rspec-mocks (3.0.2)
+      rspec-support (~> 3.0.0)
+    rspec-support (3.0.2)
 
 PLATFORMS
   ruby
 
 DEPENDENCIES
-  minitest (= 5.3)
+  minitest (= 5.4.1)
   minitest-colorize
-  mocha (= 0.14.0)
+  mocha (= 1.1.0)
   rake
+  rspec (~> 3.0.0)