Include account shadow files in the backup

On cPanel servers (possibly others too), some files (like passwd and shadow) from /home/*/etc/* are missing from JB5 backup by design.

This generates a huge (albeit edge case) problem: if a customer restores the /home/*/etc folder without using "Merge", the shadow file will end up missing from the account, thus no email accounts will have passwords set. This will render the email account inactive / unusable even from Webmail and missing from cPanel -> Email Accounts. In this case probably the only solution is to restore the email account but this might be unfeasible in some cases (users with a lot of email accounts or email account with a lot of data).

Please update JB5 to include all files from the user homedir into the backup without exception.