Update compatiblity to 4.0

git-svn-id: https://plugins.svn.wordpress.org/simple-content-experiments/trunk@993323 b8457f37-d9ea-0310-8a92-e5e31aec5664
Tagged release 2.3 (993323)

git-svn-id: https://plugins.svn.wordpress.org/simple-content-experiments/trunk@993326 b8457f37-d9ea-0310-8a92-e5e31aec5664