Service worker building (but not quite right yet)

missing-types.d.ts

@@ -27,6 +27,11 @@ declare module 'css:*' {
   export default source;
 }
 
+declare module 'data-url:*' {
+  const url: string;
+  export default url;
+}
+
 declare var ga: {
   (...args: any[]): void;
   q: any[];