Build: remove dependency on grunt-contrib-concat

Author: arschmitz

package.json

@@ -55,7 +55,6 @@
 		"grunt": "0.4.2",
 		"grunt-bowercopy": "1.1.0",
 		"grunt-compare-size": "0.4.0",
-		"grunt-contrib-concat": "0.1.3",
 		"grunt-contrib-csslint": "0.2.0",
 		"grunt-contrib-jshint": "0.7.1",
 		"grunt-contrib-qunit": "0.6.0",