Implement shell-style command history

[examknow]

I tend to typo a lot so it would be extremely useful if I could just press my up arrow like I would on my shell or on my normal IRC client to get the command back.

[DanielOaks]

yeah I wanna do this, see also #12, the main issues with tackling this are:

• making sure it still works on Windows (iirc I had some trouble getting windows compatibility while also implementing this sort of gui. maybe that's better now though).
• getting the 16-99 control codes working properly (we're gonna have to send our own ANSI, and this feels like a more complicated thing than doing the shell-style message typing/entry so I sorta want to tackle it first if I can).

[slingamn]

Moved to #28