Add Buster release notes

<title>News from Debian Med Blend</title>

    <para>The Debian Med team has added several new packages and updates for

    software targeting life sciences and medicine.  The effort to add

    Continuous Integration support for the packages in this field was (and

    will be) continued.

    </para><para>

    To install packages maintained by the Debian Med team, install the

    metapackages named med-*, which are at version 3.3 for Debian Buster.

    Feel free to visit the

    <ulink url="http://blends.debian.org/med/tasks">Debian Med tasks pages</ulink>

    to see the full range of biological and medical software available in Debian.

    </para>