Update gem dependencies

Gemfile.lock

@@ -22,13 +22,13 @@ GEM
     erubi (1.7.1)
     ethon (0.11.0)
       ffi (>= 1.3.0)
-    eventmachine (1.2.5)
+    eventmachine (1.2.7)
     execjs (2.7.0)
-    exifr (1.3.3)
-    ffi (1.9.23)
+    exifr (1.3.4)
+    ffi (1.9.25)
     fspath (3.1.0)
     highline (1.7.10)
-    html-pipeline (2.7.2)
+    html-pipeline (2.8.0)
       activesupport (>= 2)
       nokogiri (>= 1.4)
     i18n (1.0.1)
@@ -39,7 +39,7 @@ GEM
       image_size (~> 1.5)
       in_threads (~> 1.3)
       progress (~> 3.0, >= 3.0.1)
-    image_optim_pack (0.5.0.20180419)
+    image_optim_pack (0.5.1)
       fspath (>= 2.1, < 4)
       image_optim (~> 0.19)
     image_size (1.5.0)
@@ -49,7 +49,7 @@ GEM
     minitest (5.11.3)
     multi_json (1.13.1)
     mustermann (1.0.2)
-    newrelic_rpm (5.0.0.342)
+    newrelic_rpm (5.2.0.345)
     nokogiri (1.8.2)
       mini_portile2 (~> 2.3.0)
     options (2.3.2)
@@ -61,7 +61,7 @@ GEM
       coderay (~> 1.1.0)
       method_source (~> 0.9.0)
     rack (2.0.5)
-    rack-protection (2.0.1)
+    rack-protection (2.0.3)
       rack
     rack-test (1.0.0)
       rack (>= 1.0, < 3)
@@ -75,17 +75,18 @@ GEM
     sass-listen (4.0.0)
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
-    sinatra (2.0.1)
+    sinatra (2.0.3)
       mustermann (~> 1.0)
       rack (~> 2.0)
-      rack-protection (= 2.0.1)
+      rack-protection (= 2.0.3)
       tilt (~> 2.0)
-    sinatra-contrib (2.0.1)
-      backports (>= 2.0)
+    sinatra-contrib (2.0.3)
+      activesupport (>= 4.0.0)
+      backports (>= 2.8.2)
       multi_json
       mustermann (~> 1.0)
-      rack-protection (= 2.0.1)
-      sinatra (= 2.0.1)
+      rack-protection (= 2.0.3)
+      sinatra (= 2.0.3)
       tilt (>= 1.3, < 3)
     sprockets (3.7.1)
       concurrent-ruby (~> 1.0)
@@ -112,9 +113,9 @@ GEM
       ethon (>= 0.9.0)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
-    uglifier (4.1.10)
+    uglifier (4.1.11)
       execjs (>= 0.3.0, < 3)
-    unicode-display_width (1.3.2)
+    unicode-display_width (1.3.3)
     unicode_utils (1.4.0)
     unix_utils (0.0.15)
     yajl-ruby (1.4.0)