merging 1.5.1 into trunk

git-svn-id: https://plugins.svn.wordpress.org/bbpress-notify-nospam/trunk@879733 b8457f37-d9ea-0310-8a92-e5e31aec5664
rebranching 1.5

git-svn-id: https://plugins.svn.wordpress.org/bbpress-notify-nospam/branches/1.5@879735 b8457f37-d9ea-0310-8a92-e5e31aec5664