…ten#339

Now you can just M-x rename-buffer then start a new org-brain to look
at and/or manipulate the org-brain from different locations.

So far there doesn't seem to be any problems with the underlying org
files getting munged, probably because org-brain seems to immediately
save them after making changes.   There may need to be some kind of
locking if one thing was changed but not exited/saved immediately,
then another thing changed and saved, then the first thing saved.

I haven't had the time to actually check this as this is not my
workflow.

looks like the changes I did to make all vars buffer local got backed out

instead of always in insert which was annoying