Rejoining a temporarily hidden channel or query does not unhide it
If i part a channel and temporarily hide it, and later rejoin the channel, the channel stays hidden until there is activity. Auto-hiding is off. This could be considered a "missing feature" rather then a bug, but its a relevant usability issue IMHO, as it requires manually unhiding the channel again. The same applies for hidden querys (/query user should unhide it).
Tested with 0.5.1 dist-7cae1af on Win XP. (Why can't i select 0.5.1 as version?)
Unhide buffer when joining or querying and it was temporarily hidden. fixes #866