Add new action to blog copier after copy is executed.

git-svn-id: https://plugins.svn.wordpress.org/blog-copier/trunk@982078 b8457f37-d9ea-0310-8a92-e5e31aec5664
minor update to read me

git-svn-id: https://plugins.svn.wordpress.org/blog-copier/trunk@982079 b8457f37-d9ea-0310-8a92-e5e31aec5664