Update initialize method in library.rb and library_spec.rb to to pass test.
Add status method to pass test
Revise status method to pass testing.
Add check_out method to pass test
Update test to pass if status method is already set to checked out
Update library.rb to pass test for book checkin method.
Update borrower initialize method to require a name
Start library object with an empty array of books to pass testing.
Add register_new_book method to library.rb and update to pass testing.
Update library.rb to add multiple books and refactor register_new_book method.
Update library.rb to pass test allowing borrower book checkout by id.
Add get_borrower method, has bug in it.