update

Gemfile.lock

 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (5.1.3)
+    activesupport (5.1.4)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (~> 0.7)
       minitest (~> 5.1)
       tzinfo (~> 1.1)
-    addressable (2.5.1)
-      public_suffix (~> 2.0, >= 2.0.2)
+    addressable (2.5.2)
+      public_suffix (>= 2.0.2, < 4.0)
     bibtex-ruby (4.4.4)
       latex-decode (~> 0.0)
     citeproc (1.0.5)
@@ -16,7 +16,7 @@ GEM
       citeproc (>= 1.0.4, < 2.0)
       csl (~> 1.4)
     colorator (1.1.0)
-    colored (1.2)
+    colorize (0.8.1)
     concurrent-ruby (1.0.5)
     csl (1.4.5)
       namae (~> 0.7)
@@ -26,26 +26,26 @@ GEM
       ffi (>= 1.3.0)
     ffi (1.9.18)
     forwardable-extended (2.6.0)
-    html-proofer (3.7.2)
+    html-proofer (3.7.3)
       activesupport (>= 4.2, < 6.0)
       addressable (~> 2.3)
-      colored (~> 1.2)
+      colorize (~> 0.8)
       mercenary (~> 0.3.2)
       nokogiri (~> 1.7)
       parallel (~> 1.3)
       typhoeus (~> 0.7)
       yell (~> 2.0)
     i18n (0.8.6)
-    jekyll (3.5.2)
+    jekyll (3.6.0)
       addressable (~> 2.4)
       colorator (~> 1.0)
       jekyll-sass-converter (~> 1.0)
       jekyll-watch (~> 1.1)
-      kramdown (~> 1.3)
+      kramdown (~> 1.14)
       liquid (~> 4.0)
       mercenary (~> 0.3.3)
       pathutil (~> 0.9)
-      rouge (~> 1.7)
+      rouge (>= 1.7, < 3)
       safe_yaml (~> 1.0)
     jekyll-feed (0.9.2)
       jekyll (~> 3.3)
@@ -62,7 +62,7 @@ GEM
       jekyll (~> 3.3)
     jekyll-watch (1.5.0)
       listen (~> 3.0, < 3.1)
-    kramdown (1.14.0)
+    kramdown (1.15.0)
     latex-decode (0.2.2)
       unicode (~> 0.4)
     liquid (4.0.0)
@@ -70,22 +70,22 @@ GEM
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
     mercenary (0.3.6)
-    mini_portile2 (2.2.0)
+    mini_portile2 (2.3.0)
     minitest (5.10.3)
     namae (0.11.3)
-    nokogiri (1.8.0)
-      mini_portile2 (~> 2.2.0)
+    nokogiri (1.8.1)
+      mini_portile2 (~> 2.3.0)
     parallel (1.12.0)
-    pathutil (0.14.0)
+    pathutil (0.16.0)
       forwardable-extended (~> 2.6)
-    public_suffix (2.0.5)
-    rake (12.0.0)
+    public_suffix (3.0.0)
+    rake (12.1.0)
     rb-fsevent (0.10.2)
     rb-inotify (0.9.10)
       ffi (>= 0.5.0, < 2)
-    rouge (1.11.1)
+    rouge (2.2.1)
     safe_yaml (1.0.4)
-    sass (3.5.1)
+    sass (3.5.2)
       sass-listen (~> 4.0.0)
     sass-listen (4.0.0)
       rb-fsevent (~> 0.9, >= 0.9.4)
@@ -111,4 +111,4 @@ DEPENDENCIES
   rake
 
 BUNDLED WITH
-   1.15.3
+   1.15.4