[PATCH]fdo 50488 added calc formula XOR as defined in ODFF1.2

[Winfried Donkers]

Hi Eike, 

> Argh, I missed to reply to you in the bug that XOR is also in the said CWS we
> still hope to be able to integrate back from OOo times. So you duplicated
> some work, my bad. Anyway, if it's ready we'll integrate it, adding some
> pieces for Excel import/export. However, you attached a patch for DATEDIF
> instead of XOR ;-)

How stupid of me to attach the wrong patch! I will (re)submit the proper patch file later this afternoon (It is on my computer at home).
Should my work not be as good as the code you are hoping to integrate, just disregard my patch. High quality Libreoffice goes first.

> I'll browse through the list you provided, maybe there are some things to
> remark.

Yes, please do. I will wait for your remarks.

Winfried