Added functionality to all drop down selections on the Dashboard batch edit menu.  Felt like I was doing a bit of hacking as I was having trouble reverse-engineering the app so I'd understand if someone wanted to clean it up/point me in a better direction for finding the right actions in the controllers, etc.  Also commented out 'Edit Selection' and 'Delete Selection' buttons in _sort_and_per_page.html.erb as I felt it might be redundant with the same options in the batch edit drop down.
Adding batch remove from collection. fixes #3765
Returning styling for buttons in dashboard drop down