Mass bugfiling potential: bundled implementation of md5

[Yangfl <mmyangfl@gmail.com>]

Hi,

Many of packages include bundled Aladdin Enterprises independent
implementation of md5. Full list can be seen at
https://codesearch.debian.net/search?q=typedef+unsigned+char+md5_byte_t&perpkg=1
(100 packages)

As discussed in #909116, libmd-dev now provides a compatible interface
for that, so bundled sources should be dropped.

A potential fix for that might be replace the md5.h header with

#define LIBMD_MD5_ALADDIN
#include <md5.h>

remove building for md5.c, and add

Build-Depends: libmd-dev (>= 1.0.1)

Thanks,