zkclient: rooms were forcibly-focused as user joined

[jrick]

A user accepted the invites to join several rooms I was already in, and i saw zkclient focus to each room as the user joined, writing the join event to the room's history. Expected behavior is to write the join message to the room without taking focus away from the current room.

zkclient was built at these module versions:

$ go version -m $(which zkclient) 
/home/jrick/go/bin/zkclient: go1.13.1
        path    github.com/companyzero/zkc/zkclient
        mod     github.com/companyzero/zkc      v0.3.2-0.20190930150657-6371f4a8c163    h1:v8YGKlGMwwVV4ytVxb11KdgGanzzPTW+w9629BM2IoI=
        dep     github.com/companyzero/sntrup4591761    v0.0.0-20190320150934-1ea2d0911e48      h1:5J5+W6LVdeJeHzqrNARVzXGD/u0jqZ+yiFYWhkHMnts=
        dep     github.com/companyzero/ttk      v0.0.0-20190917162001-c1cf7497538d      h1:6g6nVCvFM/jcD5jzY009UoxRcU18EX3S26TDYqmm9nY=
        dep     github.com/davecgh/go-spew      v1.1.1  h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
        dep     github.com/davecgh/go-xdr       v0.0.0-20161123171359-e6a2ba005892      h1:qg9VbHo1TlL0KDM0vYvBG9EY0X0Yku5WYIPoFWt8f6o=
        dep     github.com/marcopeereboom/goutil        v0.0.0-20151009174051-30a0823e951a      h1:bun2ZPCPdMmRb3q7CGAWIW/AbpSF5V/8oQC+J/M68gs=
        dep     github.com/mattn/go-runewidth   v0.0.4  h1:2BvfKmzob6Bmd4YsL0zygOqfdFnK7GR4QL06Do4/p7Y=
        dep     github.com/mitchellh/go-homedir v1.1.0  h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
        dep     github.com/nsf/termbox-go       v0.0.0-20190817171036-93860e161317      h1:hhGN4SFXgXo61Q4Sjj/X9sBjyeSa2kdpaOzCO+8EVQw=
        dep     github.com/vaughan0/go-ini      v0.0.0-20130923145212-a98ad7ee00ec      h1:DGmKwyZwEB8dI7tbLt/I/gQuP559o/0FrAkHKlQM/Ks=
        dep     golang.org/x/crypto     v0.0.0-20190927123631-a832865fa7ad      h1:5E5raQxcv+6CZ11RrBYQe5WRbUIWpScjh0kvHZkZIrQ=