added upgrade notice and what does this plugin do

git-svn-id: https://plugins.svn.wordpress.org/dpabadbotwp/trunk@988809 b8457f37-d9ea-0310-8a92-e5e31aec5664
fixed error in comments

git-svn-id: https://plugins.svn.wordpress.org/dpabadbotwp/trunk@988810 b8457f37-d9ea-0310-8a92-e5e31aec5664