re-design permission pre-check for froster index

[dirkpetersen]

before froster index is submitted to cluster to do a parallel pwalk another function is run :

_is_correct_files_folders_permissions

This function has 2 problems:

• it is not run in parallel like pwalk and it can take weeks before pwalk will even get started
• it is not capturing os.walk errors

[victormachadoperez]

You are right. This function uses os.walk but not pwalk, so it is unsuitable for large HPC systems.

_is_correct_files_folders_permissions function has been deleted from froster {index|archive|delete|restore} commands for the same reason.

The function is not used but is still implemented in case we implement a "walk solution" in the future.

Wherever os.walk is used, it captures and prints the os.walk errors.

Also, I improved the print_error() output so it specifically captures PermissionError or "ReadError" and "WriteError" exceptions and leads the user to use froster archive --permissions /folder/path to check permission issues with a given folder.

This is fixed in froster v0.14.5