added link til TablePress

git-svn-id: https://plugins.svn.wordpress.org/tablepress-chartist/trunk@1005596 b8457f37-d9ea-0310-8a92-e5e31aec5664
In "Installation", added link til TablePress

git-svn-id: https://plugins.svn.wordpress.org/tablepress-chartist/trunk@1005599 b8457f37-d9ea-0310-8a92-e5e31aec5664