v1.7.6

git-svn-id: https://plugins.svn.wordpress.org/wp-performance-pack/trunk@931282 b8457f37-d9ea-0310-8a92-e5e31aec5664
added changelog

git-svn-id: https://plugins.svn.wordpress.org/wp-performance-pack/trunk@931284 b8457f37-d9ea-0310-8a92-e5e31aec5664