The following forms are supported in $account, with groups separated by a
literal colon. All account and network name matching is currently case sensitive:
$account -> Returns True (a match) if the target is registered.
$account:accountname -> Returns True if the target's account name matches the one given, and the target is connected to the local network..
$account:accountname:netname -> Returns True if both the target's account name and origin network name match the ones given.
$account:*:netname -> Matches all logged in users on the given network.
