doc: update help of command /disconnect in user guide

doc/de/autogen/user/irc_commands.txt

@@ -143,11 +143,12 @@ Ziel: Servername
 [[command_irc_disconnect]]
 [command]*`disconnect`* Verbindung zu einem oder mehreren IRC-Server(n) trennen::
 ........................................
-/disconnect  [<server>|-all [<reason>]]
+/disconnect  [<server>|-all|-pending [<reason>]]
 
-server: Name des Servers zu dem die Verbindung getrennt werden soll
-  -all: Verbindung zu allen Servern trennen
-reason: Begründung der Trennung
+  server: server name to disconnect
+    -all: disconnect from all servers
+-pending: cancel auto-reconnection on servers currently reconnecting
+  reason: reason for quit
 ........................................
 
 [[command_irc_halfop]]

doc/en/autogen/user/irc_commands.txt

@@ -143,11 +143,12 @@ target: server name
 [[command_irc_disconnect]]
 [command]*`disconnect`* disconnect from one or all IRC servers::
 ........................................
-/disconnect  [<server>|-all [<reason>]]
+/disconnect  [<server>|-all|-pending [<reason>]]
 
-server: server name to disconnect
-  -all: disconnect from all servers
-reason: reason for quit
+  server: server name to disconnect
+    -all: disconnect from all servers
+-pending: cancel auto-reconnection on servers currently reconnecting
+  reason: reason for quit
 ........................................
 
 [[command_irc_halfop]]

doc/fr/autogen/user/irc_commands.txt

@@ -143,11 +143,12 @@ cible: nom du serveur
 [[command_irc_disconnect]]
 [command]*`disconnect`* se déconnecter d'un ou de tous les serveurs IRC::
 ........................................
-/disconnect  [<serveur>|-all [<raison>]]
+/disconnect  [<serveur>|-all|-pending [<raison>]]
 
-serveur: nom du serveur pour se déconecter
-   -all: se déconnecter de tous les serveurs
- raison: raison pour le quit
+ serveur: nom du serveur pour se déconecter
+    -all: se déconnecter de tous les serveurs
+-pending: annuler la reconnexion automatique sur les serveurs en cours de reconnexion
+  raison: raison pour le quit
 ........................................
 
 [[command_irc_halfop]]

doc/it/autogen/user/irc_commands.txt

@@ -143,11 +143,12 @@ destinazione: nome server
 [[command_irc_disconnect]]
 [command]*`disconnect`* disconnette da uno o tutti i server IRC::
 ........................................
-/disconnect  [<server>|-all [<motivo>]]
+/disconnect  [<server>|-all|-pending [<reason>]]
 
-server: nome del server da cui disconnettersi
-  -all: disconnette da tutti i server
-motivo: motivo per la disconnessione
+  server: server name to disconnect
+    -all: disconnect from all servers
+-pending: cancel auto-reconnection on servers currently reconnecting
+  reason: reason for quit
 ........................................
 
 [[command_irc_halfop]]