Update gem dependencies

Gemfile.lock

@@ -18,13 +18,13 @@ GEM
       coffee-script-source
       execjs
     coffee-script-source (1.9.1)
-    daemons (1.1.9)
+    daemons (1.2.1)
     erubis (2.7.0)
     ethon (0.7.3)
       ffi (>= 1.3.0)
     eventmachine (1.0.7)
-    execjs (2.3.0)
-    ffi (1.9.6)
+    execjs (2.4.0)
+    ffi (1.9.7)
     highline (1.6.21)
     hike (1.2.3)
     html-pipeline (1.11.0)
@@ -35,7 +35,7 @@ GEM
     method_source (0.8.2)
     mini_portile (0.6.2)
     minitest (5.5.1)
-    multi_json (1.10.1)
+    multi_json (1.11.0)
     nokogiri (1.6.6.2)
       mini_portile (~> 0.6.0)
     options (2.3.2)
@@ -53,7 +53,7 @@ GEM
       rack (>= 1.0)
     rake (10.4.2)
     rr (1.1.2)
-    sass (3.4.12)
+    sass (3.4.13)
     sinatra (1.4.5)
       rack (~> 1.4)
       rack-protection (~> 1.4)
@@ -78,13 +78,13 @@ GEM
       eventmachine (~> 1.0)
       rack (~> 1.0)
     thor (0.19.1)
-    thread_safe (0.3.4)
+    thread_safe (0.3.5)
     tilt (1.4.1)
     typhoeus (0.7.1)
       ethon (>= 0.7.1)
     tzinfo (1.2.2)
       thread_safe (~> 0.1)
-    uglifier (2.7.0)
+    uglifier (2.7.1)
       execjs (>= 0.3.0)
       json (>= 1.8.0)
     unix_utils (0.0.15)