Add modals for signin, signup and logout
Amazon signature generation
Merge pull request #1 from zestos/master

Amazon signature generation
nokogiri amazon_attrib scrape added to book.rb, open-uri
get_amazon_attribs, batch_amazon_attribs added to retrieve all book data
Conflicts resolved
Merge branch 'master' of https://github.com/margaretblue/booklust

Conflicts:
	app/models/book.rb