Added a way to hide individual link actions like "Dismiss" and "Unlink". Now there's a "Show link actions" setting under "Settings -> Link Checker -> Advanced". By default all applicable actions are visible.

Also moved the "Recheck" action to the end of the list.

git-svn-id: https://plugins.svn.wordpress.org/broken-link-checker/trunk@1027993 b8457f37-d9ea-0310-8a92-e5e31aec5664