imap-send: Tell cURL to use imap:// or imaps://

Right now the imap:// or imaps:// part of imap.host is not being
passed on to cURL.  Perhaps it was able to guess correctly under some
circumstances, but I was not able to find one; it was just trying to
make HTTP requests for me.  It’s better to be explicit in any case.

Signed-off-by: Anders Kaseorg <andersk@mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

imap-send.c

@@ -1410,6 +1410,7 @@ static CURL *setup_curl(struct imap_server_conf *srvc)
 	curl_easy_setopt(curl, CURLOPT_USERNAME, server.user);
 	curl_easy_setopt(curl, CURLOPT_PASSWORD, server.pass);
 
+	strbuf_addstr(&path, server.use_ssl ? "imaps://" : "imap://");
 	strbuf_addstr(&path, server.host);
 	if (!path.len || path.buf[path.len - 1] != '/')
 		strbuf_addch(&path, '/');