======Synopsis:======
[[on]] [<modes>]list [<serial#>] [-|^]<match> { <action> }

======Description:======
This hook is triggered whenever the client receives server output from
the [[LIST]] command.  Any individual line of output can trigger the hook.

======Parameters:======
|$0    |channel name |
|$1    |number of users on the channel |
|$2-   |channel topic (if any) |

======Examples:======
To limit output to channels with a topic:
   on ^list "*" {
      if ( [$2] ) {
         xecho -b $[$CHANNEL_NAME_WIDTH]0 $[-2]1 $2-
      }
   }