Fix bug with published related policies.

Mapping to #latest_edition then filtering by
published will get you false negatives if the
policy has a newer unpublished edition.
Only show latest doc collections in speed tagger

Previously all editions of every document collection were being shown
which meant the same document collection would show multiple times with
no indication which should be chosen. This change makes only the latest
edition for each document collection display.
Fix copy style on detailed guides admin

https://www.pivotaltracker.com/s/projects/367813/stories/58900462
Merge pull request #1066 from alphagov/fix-document-collection-speed-tagging

Only show latest doc collections in speed tagger
Previously all editions of every document collection were being shown
which meant the same document collection would show multiple times with
no indication which should be chosen. This change makes only the latest
edition for each document collection display.

Further fix for https://www.pivotaltracker.com/story/show/59242784
Merge pull request #1067 from alphagov/58900462-fix-detailed-guide-copy-style

Fix copy style on detailed guides admin

https://www.pivotaltracker.com/s/projects/367813/stories/58900462
Merge pull request #1059 from alphagov/policy-weirdness

Fix bug with published related policies.



https://www.pivotaltracker.com/story/show/60688864

Mapping to #latest_edition then filtering by published will get you false negatives if the policy has a newer unpublished edition.

This is exacerbated by the unnatural conversion to editions when really the editions are linked to documents. See the tech debt around the edition/document conflux.