Fix too-long feedmail-sendmail-f-doesnt-sell-me-out doc string

* lisp/mail/feedmail.el (feedmail-sendmail-f-doesnt-sell-me-out):
Fold the example SMTP header using continuation folding.

diff --git a/lisp/mail/feedmail.el b/lisp/mail/feedmail.el
index 2907093ea716e34a7c4cfc8cbd30b87d62511b6d..ce5a57e2283a64d08910ab32fe2fe98f7fcd5ac2 100644 (file)
--- a/lisp/mail/feedmail.el
+++ b/lisp/mail/feedmail.el
@@ -628,16 +628,19 @@ address via a command line option, \"-f\".  Unfortunately, it also has a widely
 disliked default behavior of selling you out if you do that by inserting
 an unattractive warning in the headers.  It looks something like this:
 
-  X-Authentication-Warning: u1.example.com: niceguy set sender to niceguy@example.com using -f
-
-It is possible to configure sendmail to not do this, but such a reconfiguration
-is not an option for many users.  As this is the default behavior of most
-sendmail installations, one can mostly only wish it were otherwise.  If feedmail
-believes the sendmail program will sell you out this way, it won't use the \"-f\"
-option when calling sendmail.  If it doesn't think sendmail will sell you out,
-it will use the \"-f\" \(since it is a handy feature).  You control what
-feedmail thinks with this variable.  The default is nil, meaning that feedmail
-will believe that sendmail will sell you out."
+  X-Authentication-Warning: u1.example.com: niceguy set
+      sender to niceguy@example.com using -f
+
+It is possible to configure sendmail to not do this, but such a
+reconfiguration is not an option for many users.  As this is the
+default behavior of most sendmail installations, one can mostly
+only wish it were otherwise.  If feedmail believes the sendmail
+program will sell you out this way, it won't use the \"-f\"
+option when calling sendmail.  If it doesn't think sendmail will
+sell you out, it will use the \"-f\" \(since it is a handy
+feature).  You control what feedmail thinks with this variable.
+The default is nil, meaning that feedmail will believe that
+sendmail will sell you out."
   :version "24.1"
   :group 'feedmail-headers
   :type 'boolean