provide a "safe search" backend and allow for self-censorship using nsfw or adult profile keywords. Eventually the directories will be forced to mark adult profiles and sync this knowledge between them. At the moment there's no way to do an unsafe search, but we really just need a checkbox and pass the value through directory to dirsearch on the back end, and some will want this as a pconfig.
Merge https://github.com/friendica/red into zpull