Relaxed restrictions:
- Automation posts are not validated for similarity. This was causing
error when PMs were created by regular user with same content and sent
to different users.
- Don't create warning logs when PM target does not exist anymore. When
for example spammer was deleted, delayed PM is not sent, but it is
correct behaviour;
- Allow tags to be applied even if an automation user is not allowed to
tag;
- Restricted category tags should be visible in configuration UI. Still,
they will be applied only when specific topic belongs to correct
category.
