Fixing the readme

git-svn-id: https://plugins.svn.wordpress.org/breadcrumb-navxt/trunk@779331 b8457f37-d9ea-0310-8a92-e5e31aec5664
More readme.txt fixes

git-svn-id: https://plugins.svn.wordpress.org/breadcrumb-navxt/trunk@779333 b8457f37-d9ea-0310-8a92-e5e31aec5664