[tex-live] TEXMFHOME when using install-tl on a Mac

[Karl Berry]

    We can in *principle* set the installer up that when it is running
    on Mac it selects ~/Library/texmf as TEXMFHOME and maybe the other
    changes, too.

I don't like it.  I think the defaults in install-tl should not depend
on the current platform.  The whole point of native TL is to be as
consistent as possible across platforms.  I recognize there is this very
strong ~/Library convention on Macs, but still, my opinion remains
unaltered.  Sorry.

karl