Mailgraph on Debian/stable

Here we have the distinct advantage that the maintainer of the Debian mailgraph package is Norbert Tretowski the same person who runs backports.org . We can therefore use his own backport to woody and be assured that it should be updated with the same care as the sarge/sid package.

### create /opt and its user
# cat >> /etc/apt/sources.list << 'EOF'
deb     http://debian.ethz.ch/mirror/debian-backports/debian woody mailgraph
deb-src http://debian.ethz.ch/mirror/debian-backports/debian woody mailgraph
EOF
# apt-get update
# apt-get install mailgraph