Need to use html entities in the readme.txt

git-svn-id: https://plugins.svn.wordpress.org/advanced-excerpt/trunk@929325 b8457f37-d9ea-0310-8a92-e5e31aec5664
Another instanced where html entities are required

git-svn-id: https://plugins.svn.wordpress.org/advanced-excerpt/trunk@929326 b8457f37-d9ea-0310-8a92-e5e31aec5664