[Libreoffice] Approaches to enable international number format import/export in Calc

l10n
#1

OK. Let me propose a better patch (attached) using the first approach. Also
attach to the bug : https://bugs.freedesktop.org/show_bug.cgi?id=33089

This only to enable the conversion of Thai buddhist calendar and Thai native
numeral between Excel and Calc. I wish I could add more support for other
locale's but we need inputs from developers in each locale that define their
own calendars and native numerals.

So please share your locale specific details or reference materials. (sorry
for cross-posting)