Update gem dependencies

Fixes #54

Gemfile.lock

@@ -29,7 +29,7 @@ GEM
     ffi (1.9.3)
     highline (1.6.20)
     hike (1.2.3)
-    html-pipeline (1.2.0)
+    html-pipeline (1.5.0)
       activesupport (>= 2)
       nokogiri (~> 1.4)
     i18n (0.6.9)
@@ -51,7 +51,7 @@ GEM
       method_source (~> 0.8)
       slop (~> 3.4)
     rack (1.5.2)
-    rack-protection (1.5.1)
+    rack-protection (1.5.2)
       rack
     rack-test (0.6.2)
       rack (>= 1.0)