Changed compatible version to 4.0

git-svn-id: https://plugins.svn.wordpress.org/backend-startpage-customizer/trunk@988956 b8457f37-d9ea-0310-8a92-e5e31aec5664
Changed compatible version to 4.0

git-svn-id: https://plugins.svn.wordpress.org/backend-startpage-customizer/trunk@988961 b8457f37-d9ea-0310-8a92-e5e31aec5664