patchsend-email: don't duplicate Reply-to: in intro message

> If I run
>
>   git send-email --compose --reply-to 'ME <my@address.net>' .....
>
> and edit the intro message, then it will get two copies of the Reply-To
> field.  gmail.com rejects such messages.
>
> This happens because send-email reads the edited message examining the
> headers.  For recognised headers the content is extract to use in
> constructing the final message and for possible inclusion in the patch
> emails.  Unrecognised headers are gathered (in @xh) to be passed though
> uninterpreted.

> Unfortunately "Reply-To" is not recognised in this process so it is
> added to @xh as an uninterpreted header, but also generated from the
> $reply_to variable in gen_header(), resulting in two copies
>
> So:
>
> Add parsing to the loop in pre_process_file() to recognise a Reply-to
> header and to store the result in $reply_to.  This means that the
> intro message will not get a second header and also means that
> any changes made to the Reply-To header during editing will be
> incorporated in the $reply_to variable and so included in all the
> generated email messages.
>
> Signed-off-by: NeilBrown <neil@brown.name>

> Add parsing to the loop in pre_process_file() to recognise a Reply-to
> header and to store the result in $reply_to.  This means that the
> intro message will not get a second header and also means that
> any changes made to the Reply-To header during editing will be
> incorporated in the $reply_to variable and so included in all the
> generated email messages.
>
> Signed-off-by: NeilBrown <neil@brown.name>
> ---
>  git-send-email.perl | 3 +++
>  1 file changed, 3 insertions(+)

>
> diff --git a/git-send-email.perl b/git-send-email.perl
> index 437f8ac46a85..e2248c223119 100755
> --- a/git-send-email.perl
> +++ b/git-send-email.perl
> @@ -1931,6 +1931,9 @@ sub pre_process_file {
>  					$in_reply_to = $1;
>  				}
>  			}
> +			elsif (/^Reply-To: (.*)/i) {
> +				$reply_to = $1;
> +			}
>  			elsif (/^References: (.*)/i) {
>  				if (!$initial_in_reply_to || $thread) {
>  					$references = $1;