shorten readme.txt

git-svn-id: https://plugins.svn.wordpress.org/timeline-express/trunk@1007568 b8457f37-d9ea-0310-8a92-e5e31aec5664
update donation link in readme.txt

git-svn-id: https://plugins.svn.wordpress.org/timeline-express/trunk@1007569 b8457f37-d9ea-0310-8a92-e5e31aec5664