tdf#50950 sort out Calc (ISO)WEEKNUM functions

[Winfried Donkers]

Hi Eike,

I checked the function definitions for WEEKNUM and ISOWEEKNUM, for ODFF and Excel. ODFF and Excel are as good as identical, except that Excel may experience problems when the date value is entered is text.
I intend to ignore that difference and support both WEEKNUM and ISOWEEKNUM in Calc.
As you know, the problem is that the ODFF function name ISOWEEKNUM is currently used for a function with WEEKNUM functionality.

I propose to put right in 2 steps:
LO version 4.5:
UI		ODFF			ODFF-'legacy'		Excel
WEEKNUM	WEEKNUM		ISOWEEKNUM			WEEKNUM
ISOWEEKNUM	ISOWEEKNUM_TMP					ISOWEEKNUM
and remove UI WEEKNUM_ADD

LO version 4.6:
UI		ODFF			ODFF-'legacy'		Excel
WEEKNUM	WEEKNUM		WEEKNUM			WEEKNUM
ISOWEEKNUM	ISOWEEKNUM		ISOWEEKNUM_TMP		ISOWEEKNUM

Any suggestions/objections etc. before I start changing the code?

Winfried