def user_auth_link(redirect_url, options = {})
      options = { scope: DEFAULT_OAUTH_SCOPE }.merge(options)
      @auth.user_auth_link(redirect_url, options)
    end
def user_auth_link(redirect_url, options = {})
      options = { scope: DEFAULT_OAUTH_SCOPE }.merge(options)
      @auth.user_auth_link(redirect_url, options)
    end
Public: Generates a URL to send the user to in order to perform the OAuth
 2.0 authorization process.

 redirect_uri - A String specifing the URI to return the user to once they
                have completed the authorization steps.
 options      - The Hash options used to refine the selection
                (default: {}):
                :scope - Array or String of scopes describing the access to
                         request from the user to the users calendars
                         (default: DEFAULT_OAUTH_SCOPE).
                :state - Array of states to retain during the OAuth
                         authorization process (optional).

 See http://www.cronofy.com/developers/api#authorization for reference.

 Returns the URL as a String.