Add VFS-License-clarification.txt as discussed on the Team list.

Update WHATSNEW.txt with a copy for the next release.

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>

Autobuild-User(master): Ralph Böhme <slow@samba.org>
Autobuild-Date(master): Thu Oct 22 15:34:54 UTC 2020 on sn-devel-184
