Doesn't update buffer list after `ido-kill-buffer-at-head`

[alanpearce]

With ido-mode enabled for buffers, pressing C-k whilst in the buffer list will kill a buffer and remove it from the list.

With flx-ido enabled, the buffer is still killed, but it's still part of the list. On the next invocation, the buffer is no longer there (as expected).

Is it possible to make it so that killing a buffer from inside the list removes it from that list?

[lewang]

this is a real bug, dupe of #46