Update Readme.txt File

git-svn-id: https://plugins.svn.wordpress.org/amazon-product-price/trunk@968898 b8457f37-d9ea-0310-8a92-e5e31aec5664
Update Readme.txt File

git-svn-id: https://plugins.svn.wordpress.org/amazon-product-price/trunk@968900 b8457f37-d9ea-0310-8a92-e5e31aec5664