Add notice messages to chatWindow when present

I could not see the notice messages I receive from github hooks.

So when the 'to' argument of the notice is a channel, it sends the message to that channel window instead of the status window.

I noticed by #32 that maybe the former behaviour is wanted, is there any reason for that? I can add an user setting to opt in for notices on channel room, in this case. This feature is a must for people who chat on software development related channels IMHO.

Fix #183 

BTW, thanks for all the work you've put on this, subway is awesome!