New shortcuts + "new title" placed in placeholder

'Shift+v': open target and mark read
'Shift+n': switch to newest items overview / menu item
'Shift+u': switch to unread items overview / menu item
'Shift+s': switch to starred items overview / menu item
'Shift+o': close open entries

Moved the "new title" text from the input value to a placeholder attribute (on sources page)