Consultation can move to the outcome state without attachment

The response summary (which doesn't seem to be used at the moment) is
now using govspeak and can be used to make a consultation into the
outcome state without an attachment.
Frontend design changes for the closed consultations

test for published consultation response with summary
Merge pull request #663 from alphagov/44906313-consultation-outcome

Allow a consultation to switch to outcome when a response summary is added

https://www.pivotaltracker.com/story/show/44906313