unmounting and remounting seems to fix errors

src/freedombone

   echo "  mkdir $USB_MOUNT" >> /usr/bin/$BACKUP_SCRIPT_NAME
   echo -n '  mount $USB_DRIVE ' >> /usr/bin/$BACKUP_SCRIPT_NAME
   echo "$USB_MOUNT" >> /usr/bin/$BACKUP_SCRIPT_NAME
+  echo "  umount $USB_MOUNT" >> /usr/bin/$BACKUP_SCRIPT_NAME
+  echo -n '  mount $USB_DRIVE ' >> /usr/bin/$BACKUP_SCRIPT_NAME
+  echo "$USB_MOUNT" >> /usr/bin/$BACKUP_SCRIPT_NAME
   echo '  if [ ! "$?" = "0" ]; then' >> /usr/bin/$BACKUP_SCRIPT_NAME
   echo "    echo 'There was a problem mounting the USB drive to $USB_MOUNT'" >> /usr/bin/$BACKUP_SCRIPT_NAME
   echo "    rm -rf $USB_MOUNT" >> /usr/bin/$BACKUP_SCRIPT_NAME