Bug 18900: wrong number format in receiving order

Bug 18900: wrong number format in receiving order

Bug 18471 added number formating in order receive.

I found a bug generated by this.
Koha::Number::Price defines methods to (un)format price depending on CurrencyFormat syspref.
The bug is that for CurrencyFormat US, some params are not defined in this module so there are retrieved from system locale. If system locale is not en_US, the params will be wrong. For example fr_FR will define ',' as decimal and so saved unit price is divided by 1000.

To recreate:
- On a server with locale 'fr_FR'
- With Plack mode
- Set CurrencyFormat on 'US'
- Open a basket
- Place an order for an item
- Close basket
- Receive order with changing 'Actual Cost' to '1,234'
- Note the 'Actual Cost' is now '1.23'
- Run unit test t/Number/Price.t without and with patch

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>