Log Message:
gallery-dl: Update to 1.18.4

Changes:
1.18.4
------
### Additions
 - [420chan] add `thread` and `board` extractors
 - [deviantart] add `tag` extractor
 - [deviantart] add `comments` option
 - [deviantart] implement a `auto-watch` option
 - [foolfuuka] add `gallery` extractor
 - [furaffinity] expand URL pattern for searches
 - [kemonoparty] automatically generate required DDoS-GUARD cookies
 - [nhentai] add `favorite` extractor
 - [shopify] support windsorstore.com
 - [twitter] add `url` to user objects
 - [twitter] expand t.co links in user descriptions
 - show a warning if an extractor doesn`t yield any results
 - add a `j` format string conversion
 - implement a `fallback` option
 - implement a `path-strip` option

### Changes
 - [shopify] use API for product listings
 - update default User-Agent headers

### Fixes
 - [deviantart] prevent exceptions for "empty" videos
 - [exhentai] improve image limits check
 - [inkbunny] fix extraction
 - [mangadex] prevent exceptions for manga without English title
 - [oauth] use defaults when config values are set to `null`
 - [pixiv] fix pixivision title extraction
 - [reddit] delay RedditAPI initialization
 - [twitter] improve error reporting
 - [twitter] fix issue when filtering quote tweets
 - [twitter] fix `logout` option

### Removals
 - [deviantart] remove the "you need session cookies to download mature \ 
scraps" warning
 - [foolslide] remove entry for kobato.hologfx.com