fdo57180 add function NUMBERVALUE() to calc as defined in ODFF1.2

[Winfried Donkers]

Hi Eike,

> http://www.w3.org/TR/xmlschema-2/#float
> Note however that our data type is double, not float, so
> http://www.w3.org/TR/xmlschema-2/#double
> [...]
> See above ;-)  and sal/inc/rtl/math.hxx

Thank you! I will use your information and probaly submit a patch soon :)

Winfried