icons for WordPress 4.0 plugin installer

git-svn-id: https://plugins.svn.wordpress.org/piklist/trunk@972509 b8457f37-d9ea-0310-8a92-e5e31aec5664
remove old icons

git-svn-id: https://plugins.svn.wordpress.org/piklist/trunk@972522 b8457f37-d9ea-0310-8a92-e5e31aec5664