javascript-101/objects.js: closing ``` in last section

Closes gh-596

bad rendering going on here:

http://learn.jquery.com/javascript-101/objects/#iterating-over-the-enumerable-properties-of-an-object

Author: rgarcia-herrera

page/javascript-101/objects.md

@@ -56,3 +56,4 @@ for ( var prop in myObject ) {
 // Property : 99999 ; value : 789
 // Property : validIdentifier ; value : 123
 // Property : some string ; value : 456
+```