Redux of #204, #283:

Right now we sort by most recently active. If I just sent a message as shazow, responding to steve. And I s<tab again, it'll complete to shazow which makes sense since it was the most recent activity but I almost never want my own name.

It should only include my name if it's the only result.

Should be a fairly small change here:

Probably need to modify the completeName helper (or inline it altogether, since it's not used anywhere else?).