Update gem dependencies

Gemfile.lock

@@ -7,12 +7,12 @@ GEM
       multi_json (~> 1.3)
       thread_safe (~> 0.1)
       tzinfo (~> 0.3.37)
-    atomic (1.1.14)
+    atomic (1.1.15)
     backports (3.6.0)
     better_errors (1.1.0)
       coderay (>= 1.0.0)
       erubis (>= 2.6.6)
-    browser (0.4.0)
+    browser (0.4.1)
     coderay (1.1.0)
     coffee-script (2.2.0)
       coffee-script-source
@@ -26,7 +26,7 @@ GEM
     eventmachine (1.0.3)
     execjs (2.0.2)
     ffi (1.9.3)
-    highline (1.6.20)
+    highline (1.6.21)
     hike (1.2.3)
     html-pipeline (1.6.0)
       activesupport (>= 2)
@@ -37,7 +37,7 @@ GEM
     mime-types (1.25.1)
     mini_portile (0.5.2)
     minitest (4.7.5)
-    multi_json (1.8.4)
+    multi_json (1.9.0)
     nokogiri (1.6.1)
       mini_portile (~> 0.5.0)
     options (2.3.2)
@@ -53,8 +53,10 @@ GEM
       rack
     rack-test (0.6.2)
       rack (>= 1.0)
+    rake (10.1.1)
     rr (1.1.2)
-    sass (3.2.14)
+    sass (3.3.0)
+      rake
     sinatra (1.4.4)
       rack (~> 1.4)
       rack-protection (~> 1.4)
@@ -74,13 +76,13 @@ GEM
       tilt (~> 1.1, != 1.3.0)
     sprockets-helpers (1.1.0)
       sprockets (~> 2.0)
-    thin (1.6.1)
+    thin (1.6.2)
       daemons (>= 1.0.9)
       eventmachine (>= 1.0.0)
       rack (>= 1.0.0)
     thor (0.18.1)
-    thread_safe (0.1.3)
-      atomic
+    thread_safe (0.2.0)
+      atomic (>= 1.1.7, < 2)
     tilt (1.4.1)
     typhoeus (0.6.7)
       ethon (~> 0.6.2)