Make README.md instruct users to install 3.0.0
Merge pull request #1056 from rspec/30-readme

Make README.md instruct users to install 3.0.0
Add necessary requires to run the project initializer
Merge pull request #1058 from rspec/fix-rails-for-3.0.0

Add necessary requires to run the project initializer
Release 3.0.1.