Merge pull request #146 from raymondfeng/master

Add the missing bind for assert

Author: doug-martin

lib/constraint.js

@@ -244,6 +244,7 @@ Constraint.extend({
             this.type = "custom";
             this.fn = func;
             this.options = options;
+            extd.bindAll(this, ["assert"]);
         },
 
         equal: function (constraint) {