= New Features

* A response_attachment plugin has been extracted from the
  sinatra_helpers plugin, allowing the use of the response.attachment
  method without having to include the rest of sinatra_helpers:

    response.attachment "a.csv"
    # content-disposition: attachment; filename="a.csv"
    # content-type: text/csv

* A send_file plugin has been extracted from the sinatra_helpers
  plugin, allowing the use of send_file without having to include the
  rest of sinatra_helpers. This allows you to return the content of a
  file as the response. It also sets the content-disposition and
  content-type headers as appropriate based on the file extension:

    send_file 'path/to/file.txt'
