If `sandbox/.emacs.d` already exists, calling `ln` again seems to create links
within this directory. Ensure that this does not happen anymore by deleting the
link first if it already exists. Also add `-T` to `ln` to ensure its arguments
are interpreted properly.
They day I understand argument interpretation in `ln` will be a good day …
This starts emacs in the local copy of the .emacs.d directory we are currently
in, by creating a new `sandbox` directory as home directory, linking the current
directory as `.emacs.d` into there, and starting emacs.
Daniel -