Backup key export isn't needed, use the keydrive command instead

src/freedombone

   gpg --import --import ${MY_BACKUP_KEY}_public.asc
   gpg --allow-secret-key-import --import ${MY_BACKUP_KEY}_private.asc
 
-  if ! grep -q "Backup key" /home/$MY_USERNAME/README; then
-      echo '' >> /home/$MY_USERNAME/README
-      echo '' >> /home/$MY_USERNAME/README
-      echo 'Backup key' >> /home/$MY_USERNAME/README
-      echo '==========' >> /home/$MY_USERNAME/README
-      echo 'GPG keys have been created which will be used for making backups' >> /home/$MY_USERNAME/README
-      echo 'These can be found in the home directory (backup_key_*.asc).' >> /home/$MY_USERNAME/README
-      echo 'You should transfer these to somewhere safe so that it can be restored.' >> /home/$MY_USERNAME/README
-  fi
-  chown $MY_USERNAME:$MY_USERNAME /home/$MY_USERNAME/README
-  chmod 600 /home/$MY_USERNAME/README
+  shred -zu ${MY_BACKUP_KEY}_public.asc
+  shred -zu ${MY_BACKUP_KEY}_private.asc
 
   echo 'configure_backup_key' >> $COMPLETION_FILE
 }