tidy book models.

I am merging without review; this is just style
make spec/features use rails_helper
all controller tests passing
commited missing schema features
Merge pull request #98 from Mattsface/add_login_to_book

Add login to book
Merge branch 'master' of github.com:Rails-Summer-Project-Noah-and-Matt/Library-Application
fix new book not owned by current user

set book.user_id in books_controller create
fix (#86)

add a sign_in user to spec/controllers/books_controller
now tests pass again
bug fixed
fixed conflicts