add link to guard gem
add "The cucumber Book" in Further Reading

Also there is a good presentation of BDD, which i recommend to everyone working with cucumber.
http://skillsmatter.com/podcast/agile-scrum/bdd-as-its-meant-to-be-done
Merge pull request #58 from markevich/add_the_cucumber_book

add "The cucumber Book" in Further Reading
Merge pull request #57 from markevich/fix_guard_gem_link

add link to guard gem
Conclude the guide on a cheerful node
add book «Everyday Rails Testing with RSpec» to Further Reading

It's good for reading. I recommend it.