Switch to our own fork of grunt-sed.

Gruntfile.js

@@ -317,6 +317,12 @@ module.exports = function (grunt) {
           return old ? RegExp.quote(old) : old;
         })(),
         replacement: grunt.option('newver'),
+        exclude: [
+          'dist/fonts',
+          'docs/assets',
+          'fonts',
+          'node_modules'
+        ],
         recursive: true
       }
     },

package.json

@@ -43,7 +43,7 @@
     "grunt-html": "~4.0.3",
     "grunt-jekyll": "~0.4.2",
     "grunt-jscs": "~1.6.0",
-    "grunt-sed": "~0.1.1",
+    "grunt-sed": "twbs/grunt-sed#v0.2.0",
     "load-grunt-tasks": "~3.1.0",
     "time-grunt": "~1.1.1"
   },