Upgrade trunk to v1.51

git-svn-id: https://plugins.svn.wordpress.org/media-library-assistant/trunk@792167 b8457f37-d9ea-0310-8a92-e5e31aec5664
Update trunk to v1.52

git-svn-id: https://plugins.svn.wordpress.org/media-library-assistant/trunk@793180 b8457f37-d9ea-0310-8a92-e5e31aec5664