Better responsive web design support

- Better proportional width/margin handling.
- [fixed] multiple timers occurred

git-svn-id: https://plugins.svn.wordpress.org/standard-widget-extensions/trunk@949975 b8457f37-d9ea-0310-8a92-e5e31aec5664
Version 1.5.1

git-svn-id: https://plugins.svn.wordpress.org/standard-widget-extensions/trunk@949976 b8457f37-d9ea-0310-8a92-e5e31aec5664