i3: introduce variables for workspace names
.xsession: switch from awesome to i3
.xsession: start xss-lock to enable screen locking by systemd
urxvt: nicer blue color
urxvt: green cursor
urxvt: enable visual bell
i3status: update every 5 seconds
urxvt: don't scroll on output while looking at scrollback buffer
i3: use "monospace" font alias, size 9