Issue 5360: Move make album cover to view screen

Ticket link: http://atutor.ca/atutor/mantis/view.php?id=5360

I have made changes in photo.php to update album cover when $_GET['album_cover'] is set and display the feedback message accordingly on "View Photo" page.
I have also commented a line in pa_edit_photos.tmpl.php which would not show the radio button on "Edit Photo" page.