add changes to readme changelog

git-svn-id: https://plugins.svn.wordpress.org/akismet/trunk@873040 b8457f37-d9ea-0310-8a92-e5e31aec5664
Abstract akismet functionality into its own class

git-svn-id: https://plugins.svn.wordpress.org/akismet/trunk@873042 b8457f37-d9ea-0310-8a92-e5e31aec5664
add folder for plugin resources

git-svn-id: https://plugins.svn.wordpress.org/akismet/trunk@873043 b8457f37-d9ea-0310-8a92-e5e31aec5664