Update gems

Gemfile.lock

@@ -1,7 +1,7 @@
 GEM
   remote: https://rubygems.org/
   specs:
-    activesupport (5.1.1)
+    activesupport (5.1.2)
       concurrent-ruby (~> 1.0, >= 1.0.2)
       i18n (~> 0.7)
       minitest (~> 5.1)
@@ -19,7 +19,7 @@ GEM
     coffee-script-source (1.12.2)
     concurrent-ruby (1.0.5)
     daemons (1.2.4)
-    erubi (1.6.0)
+    erubi (1.6.1)
     erubis (2.7.0)
     ethon (0.10.1)
       ffi (>= 1.3.0)
@@ -27,17 +27,17 @@ GEM
     execjs (2.7.0)
     ffi (1.9.18)
     highline (1.7.8)
-    html-pipeline (2.5.0)
+    html-pipeline (2.6.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
-    i18n (0.8.1)
+    i18n (0.8.4)
     method_source (0.8.2)
-    mini_portile2 (2.1.0)
+    mini_portile2 (2.2.0)
     minitest (5.10.2)
     multi_json (1.12.1)
     mustermann (1.0.0)
-    nokogiri (1.7.2)
+    nokogiri (1.8.0)
-      mini_portile2 (~> 2.1.0)
+      mini_portile2 (~> 2.2.0)
     options (2.3.2)
     progress_bar (1.1.0)
       highline (~> 1.6)
@@ -46,14 +46,14 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.8.1)
       slop (~> 3.4)
-    rack (2.0.2)
+    rack (2.0.3)
     rack-protection (2.0.0)
       rack
     rack-test (0.6.3)
       rack (>= 1.0)
     rake (12.0.0)
     rr (1.2.0)
-    sass (3.4.23)
+    sass (3.4.24)
     sinatra (2.0.0)
       mustermann (~> 1.0)
       rack (~> 2.0)
@@ -72,7 +72,7 @@ GEM
       rack (> 1, < 3)
     sprockets-helpers (1.2.1)
       sprockets (>= 2.2)
-    thin (1.7.0)
+    thin (1.7.1)
       daemons (~> 1.0, >= 1.0.9)
       eventmachine (~> 1.0, >= 1.0.4)
       rack (>= 1, < 3)