Remove the delete action link from the network admin if the plugin is active...

Remove the delete action link from the network admin if the plugin is active on the main site.  Remove the plugin(s) from the deletion list for the bulk actions and shows an error if no other plugin was selected for bulk-deletion. Props PeteMall. see #15709

git-svn-id: https://core.svn.wordpress.org/trunk@17033 1a063a9b-81f0-0310-95a4-ce76da25c4cd