Bug 16227: Fix regression from bug 15084 - select currencies correctly

Bug 16227: Fix regression from bug 15084 - select currencies correctly

This patch fixes a regression introduced by bug 15084: The currency
dropdown lists are not correctly built.
The selected currencies are wrong.

Test plan:
Create a vendor, the selected currencies should be the default one
Edit the vendor, the selected currencies should be the ones defined for
 this vendor
Create an order, the selected currency should be the 'List prices' of
 the vendor
Edit an order, the selected currency should be the one defined for this
 order

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Brendan Gallagher <bredan@bywatersolutions.com>