[PATCH] emacs: Add commentary for MELPA users

[David Bremner <david@tethera.net>]

We have a steady trickle of people using notmuch-emacs from melpa with
distro packages of notmuch, and then being confused when it doesn't
work. Try to warn people what a foot-gun this is; this commentary
should be copied to the melpa web site.
---
 emacs/notmuch.el | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/emacs/notmuch.el b/emacs/notmuch.el
index bd503a11..b112cf03 100644
--- a/emacs/notmuch.el
+++ b/emacs/notmuch.el
@@ -49,7 +49,20 @@
 ;; Have fun, and let us know if you have any comment, questions, or
 ;; kudos: Notmuch list <notmuch@notmuchmail.org> (subscription is not
 ;; required, but is available from https://notmuchmail.org).
-
+;;
+;; Note for MELPA users (and others tracking the development version
+;; of notmuch-emacs):
+;;
+;; This emacs package needs a fairly closely matching version of the
+;; notmuch program. If you use the MELPA version of notmuch.el (as
+;; opposed to MELPA stable), you should be prepared to track the
+;; master development branch (i.e. build from git) for the notmuch
+;; program as well. Upgrading notmuch-emacs too far beyond the notmuch
+;; program can CAUSE YOUR EMAIL TO STOP WORKING.
+;;
+;; TL;DR: notmuch-emacs from MELPA and notmuch from distro packages is
+;; NOT SUPPORTED.
+;;
 ;;; Code:
 
 (eval-when-compile (require 'cl))
-- 
2.13.2