Flesh out documentation for changing announces

docs/changing-announce.md

@@ -18,10 +18,20 @@ removes the old announce:
 # Shut down rTorrent
 # Backing up the session directory is recommended: tar czvf rtorrent-session-$(date -Imin).tar.gz "$(rtxmlrpc session.path)"
 cd "$(rtxmlrpc session.path)"
-chtor --reannounce "http://example.com/announce/new" *.torrent
+chtor --reannounce "https://example.com/announce/new" *.torrent --dry-run --diff # Dry-run the changes
+chtor --reannounce "https://example.com/announce/new" *.torrent                  # Run for real
+lstor  __hash__,announce *.torrent | grep example.com                            # Confirm the new URL is in place
 # Start up rTorrent
 ```
 
+!!! note
+    By default, `--reannounce` will only change the torrent
+    file if the current announce's domain or alias matches the new
+    one.  If you use `--reannounce-all` to change all torrents, it
+    will also change the `info.x_cross_seed` key, unless
+    `--no-cross-seed` is also provided
+
+
 ## Using `rtcontrol`
 
 The advantage of this method is that it doesn't require a restart of
@@ -30,5 +40,6 @@ URL directly into the item:
 
 ```bash
 rtcontrol "tracker=http://example.com/announce/old" \
-  --exec 't.multicall=0,t.disable= ; d.tracker.insert=0,"http://example.com/announce/new" ; d.save_full_session='
+  --exec 't.multicall=0,t.disable= ; d.tracker.insert=0,"https://example.com/announce/new" ; d.save_full_session='
+rtcontrol "tracker=https://example.com/announce/new" # View torrents with the new announce
 ```