BOOK API:
- create book
POST /books
curl -d '{"author":"Carpenter","title":"A day in the woods"}' -H 'Content-Type: application/json' http://localhost:8080/books- list books
GET /books
curl http://localhost:8080/books- update a book
PUT /books/:id
curl -X PUT -d '{"author":"Mrs. Carpenter","title":"A day in the woods"}' -H 'Content-Type: application/json' http://localhost:8080/books/2
- delete a book
DELETE /books/:id
curl -X DELETE http://localhost:8080/books/2