rack/rack — pull request #260 by alindeman (2011-10-25 01:33:54+00:00)
Title: Adds more Rack::Response helpers

These would be really nice, especially in RSpec tests:

```ruby
response.should be_bad_request # response.bad_request?
response.should be_unprocessable # response.unprocessable?
```

Adding `unprocessable?` also finishes #252, as noted in the commit message.