alias: add help about syntax %%command for completion of alias in /alias

doc/de/autogen/user/alias_commands.txt

@@ -3,31 +3,32 @@
 ........................................
 /alias  [-completion <completion>] <alias> [<command> [;<command>...]]
 
-completion: optionale Vervollständigung für einen Alias-Befehl (Standardverhalten: Vervollständigung wird auf den Zielbefehl angewendet)
-     alias: Name des Alias (kann mit Joker "*" beginnen oder enden um Aliase aufzulisten)
-   command: Name des zuzuordnenden Befehls (WeeChat- oder IRC-Befehl ohne führenden '/', mehrere Befehle müssen durch Semikolon getrennt werden)
+completion: completion for alias (optional, by default completion is done with target command)
+            note: you can use %%command to use completion of an existing command
+     alias: name of alias (can start or end with "*" for alias listing)
+   command: command name with arguments (many commands can be separated by semicolons)
 
-Ohne Angabe von Argumenten werden alle definierten Aliase angezeigt.
+Without argument, this command lists all defined alias.
 
-Anmerkung: Im Befehl können Variablen genutzt werden, die dann durch den entsprechenden Wert ersetzt werden:
-        $n: Argument 'n' (zwischen 1 und 9)
-       $-m: Argumente von 1 bis 'm'
-       $n-: Argumente von 'n' bis zum letzten Argument
-      $n-m: Argumente von 'n' bis 'm'
-        $*: alle Argumente
-        $~: letztes Argument
-     $nick: aktueller Nick
-  $channel: aktueller Channel
-   $server: aktueller Server
+Note: in command, special variables are replaced:
+        $n: argument 'n' (between 1 and 9)
+       $-m: arguments from 1 to 'm'
+       $n-: arguments from 'n' to last
+      $n-m: arguments from 'n' to 'm'
+        $*: all arguments
+        $~: last argument
+     $nick: current nick
+  $channel: current channel
+   $server: current server
 
-Um ein Alias zu löschen, nutze "/unalias".
+To remove an alias, use command /unalias.
 
-Beispiele:
-  Alias "/split" wird anlegt um damit ein Fenster horizontal zu teilen:
+Examples:
+  alias /split to split window horizontally:
     /alias split /window splith
-  Alias "/hallo" wird angelegt um in allen Channels, außer im #weechat Channel, den Text "Hallo" auszugeben:
-    /alias hallo /allchan -exclude=#weechat msg * Hallo
-  Alias "/forcejoin" wird angelegt um den IRC Befehl "forcejoin" mit einer Vervollständigung von /sajoin auszuführen:
+  alias /hello to say "hello" on all channels but not on #weechat:
+    /alias hello /allchan -exclude=#weechat msg * hello
+  alias /forcejoin to send IRC command "forcejoin" with completion of /sajoin:
     /alias -completion %%sajoin forcejoin /quote forcejoin
 ........................................
 

doc/en/autogen/user/alias_commands.txt

@@ -4,6 +4,7 @@
 /alias  [-completion <completion>] <alias> [<command> [;<command>...]]
 
 completion: completion for alias (optional, by default completion is done with target command)
+            note: you can use %%command to use completion of an existing command
      alias: name of alias (can start or end with "*" for alias listing)
    command: command name with arguments (many commands can be separated by semicolons)
 

doc/fr/autogen/user/alias_commands.txt

@@ -4,6 +4,7 @@
 /alias  [-completion <complétion>] alias [<commande> [;<commande>...]]
 
 complétion: complétion pour l'alias (optionnel, par défaut la complétion se fait avec la commande cible)
+            note: vous pouvez utiliser %%commande pour utiliser la complétion d'une commande existante
      alias: nom de l'alias (peut démarrer ou se terminer par "*" pour une liste d'alias)
   commande: nom de la commande avec les paramètres (plusieurs commandes peuvent être séparées par des point-virgules)
 

doc/it/autogen/user/alias_commands.txt

@@ -3,31 +3,32 @@
 ........................................
 /alias  [-completion <completamento>] <alias> [<comando> [;<comando>...]]
 
-completamento: completamento per l'alias (opzionale, per default il completamento viene eseguito con il comando di destinazione)
-        alias: nome dell'alias (può iniziare o terminare con "*" per elencare gli alias)
-      comando: nome del comando (comandi multipli vanno separati da punto e virgola)
+completion: completion for alias (optional, by default completion is done with target command)
+            note: you can use %%command to use completion of an existing command
+     alias: name of alias (can start or end with "*" for alias listing)
+   command: command name with arguments (many commands can be separated by semicolons)
 
-Senza argomento, questo comando elenca tutti gli alias definiti.
+Without argument, this command lists all defined alias.
 
-Nota: nel comando, vengono sostituite le variabili speciali:
-        $n: argomento 'n' (tra 1 e 9)
-       $-m: argomenti da 1 a 'm'
-       $n-: argomenti da 'n' all'ultimo
-      $n-m: argomenti da 'n' a 'm'
-        $*: tutti gli argomenti
-        $~: l'ultimo argomento
-     $nick: nick corrente
-  $channel: canale corrente
-   $server: server corrente
+Note: in command, special variables are replaced:
+        $n: argument 'n' (between 1 and 9)
+       $-m: arguments from 1 to 'm'
+       $n-: arguments from 'n' to last
+      $n-m: arguments from 'n' to 'm'
+        $*: all arguments
+        $~: last argument
+     $nick: current nick
+  $channel: current channel
+   $server: current server
 
-Per rimuovere un alias, usare il comando /unalias.
+To remove an alias, use command /unalias.
 
-Esempi:
-  alias /split per dividere la finestra orizzontalmente:
+Examples:
+  alias /split to split window horizontally:
     /alias split /window splith
-  alias /ciao per dire "ciao" su tutti i canali tranne #weechat:
-    /alias ciao /allchan -exclude=#weechat msg * ciao
-  alias /forcejoin per inviare il comando IRC "forcejoin" con il completamento di /sajoin:
+  alias /hello to say "hello" on all channels but not on #weechat:
+    /alias hello /allchan -exclude=#weechat msg * hello
+  alias /forcejoin to send IRC command "forcejoin" with completion of /sajoin:
     /alias -completion %%sajoin forcejoin /quote forcejoin
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