Update grunt-banner.

package.json

@@ -35,7 +35,7 @@
     "glob": "~5.0.5",
     "grunt": "~0.4.5",
     "grunt-autoprefixer": "~3.0.0",
-    "grunt-banner": "~0.3.1",
+    "grunt-banner": "~0.4.0",
     "grunt-contrib-clean": "~0.6.0",
     "grunt-contrib-compress": "~0.13.0",
     "grunt-contrib-concat": "~0.5.1",