* On /pools, hide deleted pools by default in HTML responses. Don't
filter out deleted pools in API responses.
* API change: on /forum_topics, only hide deleted forum topics by
default for HTML responses, not for API responses. Explicitly do
https://danbooru.donmai.us/forum_topics.json?search[is_deleted]=false
to filter out deleted topics.
* API change: on /tags, only hide empty tags by default for HTML
responses, not for API responses. Explicitly do
https://danbooru.donmai.us/tags.json?search[is_empty]=false to filter
out empty tags.
* API change: on /pools, default to 20 posts per page for API responses,
not 40.
* API change: add `search[is_empty]` param to /tags.json endpoint.
`search[hide_empty]=true` is deprecated in favor of `search[is_empty]=false`.
* On /pools, add option to show/hide deleted pools in search form.
* Fix the /forum_topics page putting `search[order]=sticky&limit=40` in
the URL when browsing past page 1.
Remove the creator_id field from artists, notes, and pools. The
creator_id wasn't otherwise used and was inconsistent with the
artist/note/pool history in some cases, especially for old artists.
Remove uses of the is_active flag. Keep column in database (for now).
The only purpose of this flag was to filter out pools from the pool list
in the Add to Pool dialog. This hasn't had much use since autocomplete
was added. Most pools didn't set the flag correctly anyway.
* Move all autocomplete code to autocomplete.js.
* Mark autocompleted fields with `data-autocomplete="<type>"` attributes,
instead of hardcoding input field IDs in the javascript.
