Adding a new project library with an initial class book, with interface, implementation and junits
user interface
implementation of a user
JUnit test for the user class
Added methods to library to add book, take and return book, containsBook
Book has new methods isTaken, setTaken
-added methods to library to getReaderCount(), getBookCount(), getBookBorrowedCount()
-a method which returns all users borrowing books and another for  all registered users
-a method which returns the name of a person holding a certain title