Standardize it so that all fields of type `text` are searchable with
`search[<field>_matches]`.
Before, the `<field>_matches` param was handled manually and some fields
were left out or handled inconsistently. Now it applies to all columns
of type `text`.
This does a full-text search on the field, so for example, searching
`/artist_commentaries?search[translated_description_matches]=smiling`
will match translated commentaries containing either the word "smiling",
"smiles", "smiled", or "smile".
Note that this only applies to columns defined as type `text`, not to
columns defined as `character varying`. The difference is that `text` is
used for fields containing free-form natural language, such as comments,
notes, forum posts, wiki pages, pool descriptions, etc, while `character
varying` is used for short strings not containing free-form language,
such as tag names, wiki page titles, urls, status fields, etc.
API changes:
* Add the `search[original_title_matches]`, `search[original_description_matches]`,
`search[translated_title_matches]`, `search[translated_description_matches]` params
to /artist_commentaries and /artist_commentary_versions.
* Remove the `search[name_matches]` and `search[group_name_matches]` params from /artist_versions.
* Remove the `search[title_matches]` param from /wiki_page_versions.
* Change the `search[name_matches]` param on /pools, /favorite_groups, and /pool_versions
to do a full-text search instead of a substring match.