[kbd] key definition for currency symbol

[Josef Hinteregger]

I was wrong, "currency" is ok for some other keyboard layouts.

I have found this on http://en.wikipedia.org/wiki/Currency_%28typography%29

The (currency) symbol is available on some keyboard layouts, for example
French, Danish, Norwegian and Swedish keyboards. On US International
keyboard layouts, it is obtained by AltGr + 4.

http://www.microsoft.com/globaldev/reference/keyboards.mspx
I have seen that on the US-international kbd there is a "currency" key, the
French keyboard has both keys "euro" and "currency". I will check more when
I find time.