Added a button in the details page to update existing info of authors and books

Added the 'Add' hyperlinks for author and books as well as created the forms where the user will be redirected when hyperlinks are clicked.

Updated information in README and added the new 'add' links for the Homepage

Created base and home templates and listview and detailview of both authors and books and fixed their urls and hyperlinks

Data populated in books, added get_absolute_url for bookshelf models, created templates for app

Create README.txt and the Django project