Standardizing the way licenses information is shipped in tarballs

[Pacho Ramos <pacho gentoo org>]

After some talk in:
https://bugzilla.gnome.org/show_bug.cgi?id=735882

We agree that would be really useful to standardize a place where
downstreams can check for the LICENSES of files shipped in tarball to
prevent confusions and to ensure all downstreams have proper licensing
information

What do you think?

Thanks a lot