fdo#70798 Add new Excel functions, move from add-in module?

Hi,

In Excel 2010 Microsoft introduced new functions ERF.PRECISE, ERFC.PRECISE, NETWORKDAYS.INTL and 
WORKDAY.INTL.
These functions are defined in ODF1.2 as ERF, ERFC, NETWORKDAYS and WORKDAY (some with small 
differences).
The functions ERF, ERFC, NETWORKDAYS and WORKDAY are currently in the add-in module.

I propose to make the functions fully ODF1.2 compliant (if they are not yet) and move them to the 
sc module as standard functions.
And use this code to implement the Excel 2010 functions.

IMHO the add-in module is (slowly) becoming something from the past and maintaining the function in 
the sc module is more straightforward.

Any objections to this?


Winfried