Fix for #478 - any and every should be consistent about casting result to boolean

underscore.js

@@ -180,7 +180,7 @@
     each(obj, function(value, index, list) {
       if (!(result = result && iterator.call(context, value, index, list))) return breaker;
     });
-    return result;
+    return !!result;
   };
 
   // Determine if at least one element in the object matches a truth test.