Update the 'tested up to' version.

git-svn-id: https://plugins.svn.wordpress.org/bing-boards/trunk@837974 b8457f37-d9ea-0310-8a92-e5e31aec5664
Fix a typo.

git-svn-id: https://plugins.svn.wordpress.org/bing-boards/trunk@837980 b8457f37-d9ea-0310-8a92-e5e31aec5664