update readme.txt with tags

git-svn-id: https://plugins.svn.wordpress.org/gallery-bank/trunk@992972 b8457f37-d9ea-0310-8a92-e5e31aec5664
updated tags

git-svn-id: https://plugins.svn.wordpress.org/gallery-bank/trunk@992973 b8457f37-d9ea-0310-8a92-e5e31aec5664