Extended safe deletion of file to work for directories of arbitrary depth (this used not to work due to make_directory/1's requirement that the contain directory exists).

* [DIR_EXT,SC] Renamed create_personal_[sub]directory/[0,1] for consistency.
* [DIR_EXT,EXT] Extended create_directory/1 to allow recusive creation of directories.
* [FILE_EXT,EXT] Extended safe_file_delete/1 to recursively create the directory structure in the trashcan.