Library import script

Added a script to the manage.py to import books into the library
Oh I would be very very very wary about doing this. What happens here is that foreach book we will create a new request that will get that books authors. That means we fire off another SQL query for every book. What you want to do is  edit your view here https://github.com/DUCSS/ducss-site/blob/master/project/library/views.py#L16 so that when we get all the books you also get their authors. It think it is django `prefetch` or something like that I haven't used Django in a while.