mu4e/NEWS: mention sign-signed-replies, doc update

NEWS.org

@@ -28,6 +28,9 @@
      (see docstring). E.g. when you have the "Nerd Icons" package, you can set
      this to ~nerd-icons-icon-for-file~. (1.14.1)
 
+   - ~mu4e-compose-crypto-policy~ now also recognizes ~sign-signed-replies~, to
+     automatically sign when replying to signed messages (1.14.1).
+
 *** scm
 
    - added new ~--eval~ command-line option, so you can do e.g.

mu4e/mu4e.texi

@@ -2026,6 +2026,10 @@ mu4e}.
 
 @node Signing and encrypting
 @section Signing and encrypting
+@cindex signing
+@cindex encrypting
+@cindex decrypting
+@cindex crypto
 
 Signing and encrypting of messages is possible using @ref{(emacs-mime) Top,
 emacs-mime}, most easily accessed through the @t{Attachments}-menu while
@@ -2038,6 +2042,10 @@ that draft messages are @emph{not} encrypted. So if you are using e.g.
 sure the drafts folder is @emph{not} in the set of synchronized folders, for
 obvious reasons.
 
+You can influence what messages to encrypt or sign using
+@code{mu4e-compose-crypto-policy}; see its docstring for details.
+
+
 @node Queuing mail
 @section Queuing mail