after my last rework of the copy paste code my old assumptions for the
copy paste code are no longer valid

we now behave nearly the same way as excel does

But shouldn't this stay as it was before
d330111e
in sw/source/ui/dialog/swdlgfact.cxx:1648 ?

Note that it is already included in our
readlicense_oo/txt/license.txt, so we presumably have fulfilled the
license's requirements. Just adding the text in twain.h, too, for
helpfulness.

Handle Move Sheet correctly

support copying from an unsaved document and some improvements

still problems with MoveTab and missing dialog box if we have external
refs to unsaved docs while we save

adjust named ranges formulas too

little problem here:
tab absolute and  col/row relative is tricky, the col/row is calculated
relative to the cell where the range name is used but we don't know in
which cells the range name is used
The other office solves that by making only references pointing to
sheets that are not copied external (this solution is not perfect)