LICENSE.html packaging on Mac

[Norbert Thiebaud]

on Mac we put LICENCE.html in a LICENSEs/ directory at the top level of the dmg
at the same level than the LibreOffice.app bundle

I suspect that http://cgit.freedesktop.org/libreoffice/core/commit/?id=fa424af27
broke that.. now the packager cannot find LICENSE.html

cp readlicense_oo/html/LICENSE.html setup_native/source/packinfo/.
worked around the immediate problem....

The thing is I have no idea as to by which magic the installer.pm mess
decide where to look for things...

Norbert