update several gems

Gemfile.lock

@@ -6,32 +6,30 @@ PATH
 GEM
   remote: https://rubygems.org/
   specs:
-    diff-lcs (1.2.5)
+    diff-lcs (1.3)
     docile (1.1.5)
-    json (1.8.3)
-    rake (10.4.2)
-    rdoc (4.2.2)
-      json (~> 1.4)
-    redcarpet (3.3.4)
-    rspec (3.4.0)
-      rspec-core (~> 3.4.0)
-      rspec-expectations (~> 3.4.0)
-      rspec-mocks (~> 3.4.0)
-    rspec-core (3.4.4)
-      rspec-support (~> 3.4.0)
-    rspec-expectations (3.4.0)
+    json (2.1.0)
+    rake (12.0.0)
+    rdoc (5.1.0)
+    rspec (3.6.0)
+      rspec-core (~> 3.6.0)
+      rspec-expectations (~> 3.6.0)
+      rspec-mocks (~> 3.6.0)
+    rspec-core (3.6.0)
+      rspec-support (~> 3.6.0)
+    rspec-expectations (3.6.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.4.0)
-    rspec-mocks (3.4.1)
+      rspec-support (~> 3.6.0)
+    rspec-mocks (3.6.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.4.0)
-    rspec-support (3.4.1)
-    simplecov (0.11.2)
+      rspec-support (~> 3.6.0)
+    rspec-support (3.6.0)
+    simplecov (0.15.0)
       docile (~> 1.1.0)
-      json (~> 1.8)
+      json (>= 1.8, < 3)
       simplecov-html (~> 0.10.0)
-    simplecov-html (0.10.0)
-    yard (0.8.7.6)
+    simplecov-html (0.10.2)
+    yard (0.9.9)
 
 PLATFORMS
   ruby
@@ -39,7 +37,6 @@ PLATFORMS
 DEPENDENCIES
   rake
   rdoc
-  redcarpet
   rspec
   simplecov
   yard

yawpa.gemspec

@@ -20,5 +20,4 @@ Gem::Specification.new do |gem|
   gem.add_development_dependency "rake"
   gem.add_development_dependency "rdoc"
   gem.add_development_dependency "yard"
-  gem.add_development_dependency "redcarpet"
 end