Create ${expldir}/${robot} directory if it does not exists

[k0lter]

Sometimes (while manually creating a robot) in testing or production mode, it could be useful to have this feature implemented.

1. It makes possible to load the robot configuration (from the wwsympa side) without issues even if ${expldir}/${robot} does not exists
2. It makes possible to create a first list even if ${expldir}/${robot} does not exists

Feel free to reject it if you think it is not suitable.

Maybe this PR could help people to save time.

[ikedas]

Hi @k0lter,

At the moment we have to support old-style list path ${expldir}/${listname}/ along with ${expldir}/${robot}/${listname}/ (cf. doc: See Note).

We may have to give up old-style path, and ${robot} directory will be created at the time of list creation.

[ikedas]

To keep compatibility with older style path ${expldir}/${listname}, I think this is better:

        if ($robot && (! -d "$Conf::Conf{'home'}/$robot")
            && $robot ne $Conf::Conf{'domain'}) {
            mkdir ...

in case some lists have already had ${expldir}/${name} directories.

[ikedas]

Issue #106 is a related topic.