Removes old files

git-svn-id: https://plugins.svn.wordpress.org/wp-scroll-up/trunk@955317 b8457f37-d9ea-0310-8a92-e5e31aec5664
Release 0.5.0

git-svn-id: https://plugins.svn.wordpress.org/wp-scroll-up/trunk@955319 b8457f37-d9ea-0310-8a92-e5e31aec5664