Add random filter.

Author: addyosmani

filter-random.js

@@ -0,0 +1,8 @@
+/**
+ * Return a random item in a supplied array
+ * @param  {array} array 
+ * @return {item}
+ */
+PolymerExpressions.prototype.random = function(array){
+	return array[Math.floor(Math.random() * array.length)];
+}