- For security reasons, I completely changed the handling of symbolic links:

  Symbolic links are now treated as files, no matter where they point to. The
  user is just allowed to see the path where the link points to, he is allowed
  to delete the link, to rename it and to overwrite it by renaming an other
  file. Nothing else is allowed.
  Accessing a symbolic link pointing to a directory caused also a very strange
  effect: It was possible to access this directory, but you could not access the
  objects in it.
  I had to do it in this way because of the very stupid behaviour of abs_path()
  from the Cwd module: This function is just able to detect the absolute path of
  directories.
  Hard links are not affected by this, because it is not possible to detect them
  (at least I don't know how to detect them).
- Changed the names of two error messages:
  dircopy -> dir_copy
  editdir -> dir_edit
- Fixed various errors in some template files