Update devDependencies.

package.json

@@ -30,14 +30,14 @@
     "grunt-autoprefixer": "~2.2.0",
     "grunt-banner": "~0.3.1",
     "grunt-contrib-clean": "~0.6.0",
-    "grunt-contrib-concat": "~0.5.0",
+    "grunt-contrib-concat": "~0.5.1",
     "grunt-contrib-connect": "~0.9.0",
-    "grunt-contrib-copy": "~0.7.0",
+    "grunt-contrib-copy": "~0.8.0",
     "grunt-contrib-csslint": "~0.4.0",
-    "grunt-contrib-cssmin": "~0.11.0",
+    "grunt-contrib-cssmin": "~0.12.2",
     "grunt-contrib-jshint": "~0.11.0",
     "grunt-contrib-sass": "~0.9.2",
-    "grunt-contrib-uglify": "~0.7.0",
+    "grunt-contrib-uglify": "~0.8.0",
     "grunt-contrib-watch": "~0.6.1",
     "grunt-csscomb": "~3.0.0",
     "grunt-html-validation": "~0.1.18",
@@ -45,7 +45,7 @@
     "grunt-jscs": "~1.5.0",
     "grunt-sed": "~0.1.1",
     "load-grunt-tasks": "~3.1.0",
-    "time-grunt": "~1.0.0"
+    "time-grunt": "~1.1.0"
   },
   "engines": {
     "node": ">=0.10.1"