[Alexandria-i18n-list] Small help file addition

[CHIKAMA Masaki]

Hello, Cathal.

There are two points to be added I notice for now.

1. A PNG image file is also available for book cover image.

2. The CueCat barcode scanner is never (at least for me) seen in Japan.
When using the word "barcode scanner" on book's context,  it means a
intelligent barcode reader which uses laser light and it outputs recognized
ISBN number. When using this device to add new book, you
only select ISBN field and push scanner's button to read barcode
(no need to push Enter key).
So I think it is good to add some notes about this to
"To add a book by scanning its barcode" section.

Thanks.
-- 
CHIKAMA Masaki