Bump FileSaver.js to v2015-01-04.

docs/assets/js/vendor/FileSaver.js

 /* FileSaver.js
  * A saveAs() FileSaver implementation.
- * 2014-08-29
+ * 2015-01-04
  *
  * By Eli Grey, http://eligrey.com
  * License: X11/MIT
@@ -49,9 +49,10 @@ var saveAs = saveAs
 		}
 		, force_saveable_type = "application/octet-stream"
 		, fs_min_size = 0
-		// See https://code.google.com/p/chromium/issues/detail?id=375297#c7 for
-		// the reasoning behind the timeout and revocation flow
-		, arbitrary_revoke_timeout = 10
+		// See https://code.google.com/p/chromium/issues/detail?id=375297#c7 and
+		// https://github.com/eligrey/FileSaver.js/commit/485930a#commitcomment-8768047
+		// for the reasoning behind the timeout and revocation flow
+		, arbitrary_revoke_timeout = 500 // in ms
 		, revoke = function(file) {
 			var revoker = function() {
 				if (typeof file === "string") { // file is an object URL
@@ -234,8 +235,8 @@ var saveAs = saveAs
 // while `this` is nsIContentFrameMessageManager
 // with an attribute `content` that corresponds to the window
 
-if (typeof module !== "undefined" && module !== null) {
-  module.exports = saveAs;
+if (typeof module !== "undefined" && module.exports) {
+  module.exports.saveAs = saveAs;
 } else if ((typeof define !== "undefined" && define !== null) && (define.amd != null)) {
   define([], function() {
     return saveAs;