r23706: Add a script to create domainusers,-groups and -aliases.

r23706: Add a script to create domainusers,-groups and -aliases.
This is done via rpc client. The main purpose is to
be able to fill a domain controller with a large number
of users / groups easily. A the object names are
built as <prefix><num> where number ranges from a given
start number counting up until a given number of objects
has been created.

In a next step, I will submit scripts to add (many) users to
a group and to add a user to (many) groups.

Michael