cmd/guru: emacs: store output in separate buffer

Now that we have both interactive and non-interactive uses of the guru,
we should separate the command output buffer from the display buffer.

Change-Id: I50082fdc3847c7b12869e204509141e906df3852
Reviewed-on: https://go-review.googlesource.com/20473
Reviewed-by: Alan Donovan <adonovan@google.com>
1 file changed