Readme.txt file update. Add video.

git-svn-id: https://plugins.svn.wordpress.org/custom-sidebars/trunk@964688 b8457f37-d9ea-0310-8a92-e5e31aec5664
Readme.txt file update. Add video.

git-svn-id: https://plugins.svn.wordpress.org/custom-sidebars/trunk@964691 b8457f37-d9ea-0310-8a92-e5e31aec5664