Add Visible modes function from Organisation to Users too (#16069)

You can limit or hide organisations. This pull make it also posible for users

- new strings to translte
- add checkbox to user profile form
- add checkbox to admin user.edit form
- filter explore page user search
- filter api admin and public user searches
- allow admins view "hidden" users
- add app option DEFAULT_USER_VISIBILITY
- rewrite many files to use Visibility field
- check for teams intersection
- fix context output
- right fake 404 if not visible

Co-authored-by: 6543 <6543@obermui.de>
Co-authored-by: Andrew Thornton <art27@cantab.net>

routers/api/v1/user/helper.go

@@ -17,7 +17,7 @@ func GetUserByParamsName(ctx *context.APIContext, name string) *models.User {
 	user, err := models.GetUserByName(username)
 	if err != nil {
 		if models.IsErrUserNotExist(err) {
-			if redirectUserID, err := models.LookupUserRedirect(username); err == nil {
+			if redirectUserID, err2 := models.LookupUserRedirect(username); err2 == nil {
 				context.RedirectToUser(ctx.Context, username, redirectUserID)
 			} else {
 				ctx.NotFound("GetUserByName", err)