Halfops do not get the usual "$nick added a timed ban on !@* lasting for X seconds." message, but they can place timed bans.
Additionally, when a timed ban expires on a ban that doesn't exist, every server that is linked sends the message.
I think we should just notice the channel when a user sets a timed ban, we don't hide the +b line from regular users so why hide the timed-ban line from them?
m_timedbans Notice halfops and above when a timed ban is placed
Fixes #415 reported by @killerrabbit