Add post-hook for bmo-be to update i3status

dotfiles/config/bmo/hook.ini

@@ -1,5 +1,8 @@
 [hook.au]
     post = killall -SIGUSR1 i3status
 
+[hook.be]
+    post = killall -SIGUSR1 i3status
+
 [hook.kb]
     post = killall -SIGUSR1 i3status