[PATCH 1/4] Prepare for the new sources file format

[Mathieu Bridon]

As discussed face to face and in the last releng meeting, this new
format is not great, as it breaks things for people (or scripts) try to
verify the hashes of the sources with things like:

    $ md5sum -c sources

However, md5sum (and others like sha512sum) can check files written in
the BSD-style format:

    MD5 (afile) = ahash

This format serves our purpose (having the hashtype written on the
line), and doesn't break for people using `md5sum -c sources`

Patches to move to that are coming soon, the current patch series can be
dropped.


-- 
Mathieu