Readme update.

git-svn-id: https://plugins.svn.wordpress.org/speed-booster-pack/trunk@922912 b8457f37-d9ea-0310-8a92-e5e31aec5664
Readme update.

git-svn-id: https://plugins.svn.wordpress.org/speed-booster-pack/trunk@922914 b8457f37-d9ea-0310-8a92-e5e31aec5664