Log Message:
gallery-dl: Update to 1.15.0

Changes:
1.15.0
------
### Additions
- [deviantart] support watchers-only/paid deviations (#995)
- [myhentaigallery] add gallery extractor (#1001)
- [twitter] support specifying users by ID (#980)
- [twitter] support `/intent/user?user_id=…` URLs (#980)
- add `--no-skip` command-line option (#986)
- add `blacklist` and `whitelist` options (#492, #844)
- add `filesize-min` and `filesize-max` options (#780)
- add `sleep-extractor` and `sleep-request` options (#788)
- write skipped files to archive (#550)

### Changes
- [exhentai] update wait time before original image downloads (#978)
- [imgur] use new API endpoints for image/album data
- [tumblr] create directories for each post (#965)
- support format string replacement fields in download archive paths (#985)
- reduce wait time growth rate for HTTP retries from exponential to linear

### Fixes
- [500px] update query hash
- [aryion] improve post ID extraction (#981, #982)
- [danbooru] handle posts without `id` (#1004)
- [furaffinity] update download URL extraction (#988)
- [imgur] fix image/album detection for galleries
- [postprocessor:zip] defer zip file creation (#968)

### Removals
- [jaiminisbox] remove extractors
- [worldthree] remove extractors