Added at_least_one_of parameter validator.
added a spec and documentation for default status codes
Merge pull request #701 from dspaeth-faber/document_status

added a spec and documentation for default status codes
Merge pull request #692 from dblock/at-least-one-of

Added at_least_one_of parameter validator.
Updated rspec testing for Rails in README
Merge pull request #695 from serv/readme-rspec-test

Updated rspec testing for Rails in README