nixos/postfix: document that *Alias options support comma separated values

For the longest time I thought there could be only one rootAlias.

Changed files
+5 -1
nixos
modules
services
+5 -1
nixos/modules/services/mail/postfix.nix
···
postmasterAlias = mkOption {
type = types.str;
default = "root";
-
description = "Who should receive postmaster e-mail.";
+
description = "
+
Who should receive postmaster e-mail. Multiple values can be added by
+
separating values with comma.
+
";
};
rootAlias = mkOption {
···
default = "";
description = "
Who should receive root e-mail. Blank for no redirection.
+
Multiple values can be added by separating values with comma.
";
};