Book overflow menu in library view with metadata

[Shadow53]

I'd like to be able to add an action to open a given book in KOReader, from that book's overflow menu in the library view (with "Read Now", "View Details", "Add to Collection", "Mark as unread/finished", and "Remove"). I do not think this menu is configurable from NickelMenu, and I believe #104 would need to be implemented as well to get the book's path.