Installing MAAS on trusty gives a big warning about deprecated postgresql 9.1

As shown in the integration tests: http://d-jenkins.ubuntu-ci:8080/view/MAAS/job/trusty-adt-maas-manual/ARCH=amd64,label=lenovo-RD230-01/2/console

Setting up postgresql-common (150) ...
Configuring postgresql-common
-----------------------------

Obsolete major version 9.1

The PostgreSQL version 9.1 is obsolete, but the server or client packages
are still installed. Please install the latest packages (postgresql-9.3 and
postgresql-client-9.3) and upgrade the existing clusters with
pg_upgradecluster (see manpage).

Please be aware that the installation of postgresql-9.3 will automatically
create a default cluster 9.3/main. If you want to upgrade the 9.1/main
cluster, you need to remove the already existing 9.3 cluster (pg_dropcluster
--stop 9.3 main, see manpage for details).

The old server and client packages are no longer supported. After the
existing clusters are upgraded, the postgresql-9.1 and postgresql-client-9.1
packages should be removed.

Please see /usr/share/doc/postgresql-common/README.Debian.gz for details.