Can incoming chats from users be blocked?

[Nicekiwi]

While not exactly spam, there in certainly the chance one user will harass another via the chat system. I presume setting urself as offline would make you unavailable for chat in some-way, but that's not exactly helpful in that situation.

• Are chat logs private?
• Can Admins view the logs?
• Can chat be selectively disabled for users or groups?
• What features exist for chat atm? (as of 0.3.2)