User Story 12, Add a New Book to the System

[iandouglas]

As a Visitor,
When I visit the book index page,
I see a link that allows me to add a new book.
When I click that link, I am taken to a new book path.
I can fill in a form to add a new book.
The form includes the following items:
- title
- year book was published
- number of pages (0 or higher)
- image of the book cover (optional, can be left blank)
- a list of authors (see notes below)

When I submit the form, I am taken to that book's show page.

Book titles should be converted to Title Case before saving.
Book titles should be unique within the system.
For authors, a comma-separated list of names should be entered,
and each author will be added to the database.
Authors added to the database should have their names converted
to Title Case.
Author Names should be unique within the system.
If image field is left blank, a default image should be set.

DO THESE STORIES FIRST:

• User Story 10, Book Show Page

Checklist:

• base code tests are written
• base code is written to pass tests
• edge case ("sad path") tests written
• edge case code written
• code is reviewed
• branch is merged
• all tests still pass

child of #18

child of #33

depends on #20