```ruby
require 'chronic'
require 'nokogiri'

require 'cucumber/salad/widget_container'
require 'cucumber/salad/widget_macros'
require 'cucumber/salad/conversions'
require 'cucumber/salad/instance_conversions'
require 'cucumber/salad/node_text'
require 'cucumber/salad/widget_name'
require 'cucumber/salad/widgets'
require 'cucumber/salad/table'
require 'cucumber/salad/table/mapping'
require 'cucumber/salad/table/void_mapping'
require 'cucumber/salad/table/transformations'
require 'cucumber/salad/table/cell_text'
require 'cucumber/salad/widgets/document'
require 'cucumber/salad/dsl'

class UnknownWidgetError < StandardError; end
```

Move UnknownWidgetError to Cucumber::Salad module.
user
```ruby
require 'chronic'
require 'nokogiri'

require 'cucumber/salad/widget_container'
require 'cucumber/salad/widget_macros'
require 'cucumber/salad/conversions'
require 'cucumber/salad/instance_conversions'
require 'cucumber/salad/node_text'
require 'cucumber/salad/widget_name'
require 'cucumber/salad/widgets'
require 'cucumber/salad/table'
require 'cucumber/salad/table/mapping'
require 'cucumber/salad/table/void_mapping'
require 'cucumber/salad/table/transformations'
require 'cucumber/salad/table/cell_text'
require 'cucumber/salad/widgets/document'
require 'cucumber/salad/dsl'

module Cucumber
  module Salad
    class UnknownWidgetError < StandardError; end
  end
end
```
assistant