update plugin name

git-svn-id: https://plugins.svn.wordpress.org/rocket-lazy-load/trunk@831128 b8457f37-d9ea-0310-8a92-e5e31aec5664
update plugin name

git-svn-id: https://plugins.svn.wordpress.org/rocket-lazy-load/trunk@831129 b8457f37-d9ea-0310-8a92-e5e31aec5664