install proper packages

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
release: 3.0.3

Signed-off-by: Nico Schottelius <nico@bento.schottelius.org>
python-software-properties still needed for older ubuntu versions

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
Merge branch 'issue/271' of git://github.com/asteven/cdist
++changes

Signed-off-by: Nico Schottelius <nico@bento.schottelius.org>
Merge branch 'master' into 4.0-pre-not-stable

Signed-off-by: Nico Schottelius <nico@bento.schottelius.org>

Conflicts:
	docs/changelog