Bug#932943: hex or base64

[Thomas Lange <lange@cs.uni-koeln.de>]

Hi Bastian,

in aug 2019 you wrote

> Use base64 like everyone else.
and
> Everything current switches to base64.  It's shorter and easier to see
> changes.  Hex only survives where people tend to read it.

I've checked some other distributions in may 2020. They all use hex.
They also provide checksum of all files that are available for
download. For e.g. tar.xz or uncompressed images.

https://cloud-images.ubuntu.com/focal/current/
https://cloud.centos.org/centos/7/images/
https://getfedora.org/static/checksums/Fedora-Cloud-32-1.6-x86_64-CHECKSUM

Also, since today the Debian project is still not using base64 hash sums for
their official CD/DVD images. I suggest that we provide both base64 and
hex versions of the checksum.

Maybe provide base64 and hex in our manifest but also sha{265,512}sum
hex files in the download directory on our server (petterson).

We should focus on our users and IMO users still use hex checksums.
-- 
regards Thomas