Added How does it work? to readme

git-svn-id: https://plugins.svn.wordpress.org/on-the-road/trunk@939015 b8457f37-d9ea-0310-8a92-e5e31aec5664
Minor change to readme

git-svn-id: https://plugins.svn.wordpress.org/on-the-road/trunk@939016 b8457f37-d9ea-0310-8a92-e5e31aec5664