mkhomedird: Create/remove all directories required

[PromyLOPh]

Aside from /home, we are also going to need some public workspace directory which holds projects shared with other users. We don’t want to share $HOME, as it usually contains all the dotfiles and thus sensitive data. There are two options:

1. We can either make it configureable via its currently existing config file in /etc/…
   Both, created and deleted directories must be configureable and for each of the created directories a skeleton directory must be given (but it can be empty), which is then copied.
2. Or move the actual creation into a shell script along with the current rsync /etc/skel ….
   Here for creation and deletion two different shell scripts would be run. They need to be passed the user/group of the user via arguments or the environment, so they know which directories operate on.