updating for 4.0 compat

git-svn-id: https://plugins.svn.wordpress.org/admin-bar-theme-switcher/trunk@989103 b8457f37-d9ea-0310-8a92-e5e31aec5664
removing old stylesheet

git-svn-id: https://plugins.svn.wordpress.org/admin-bar-theme-switcher/trunk@989104 b8457f37-d9ea-0310-8a92-e5e31aec5664