Eliminated the org-writers-mode minor mode, replacing it with a global
variable, a trival defun, and assigning its hooks to org-wr-guide.  Permits
half-decent teardown.  Still not perfect but a little more usable.
org-writers-room no longer turns on if point is not in an org-mode
buffer, and some of hte damage done by starting org-writers-room is
undone during teardown process.