Allow users to "stick" activity on their home page (not news feed)
Use sticky_label and unsticky_label, set to '' to not offer option
Added delete_label as option to [wps-activity] to change Settings delete text (set to '' to hide)

git-svn-id: https://plugins.svn.wordpress.org/wp-symposium-pro/trunk@912045 b8457f37-d9ea-0310-8a92-e5e31aec5664