This commit ensures that the individual Ubuntu nova
packages for any given service are only installed when that
service is configured.
This behavior was broken when RedHat support was added.
Since Redhat only has a single package, it was assumed
that all packages should always be installed on all nodes.
This was causing all services to be in a running state on
Ubuntu (b/c the packages were starting the related service)
In Debian/Ubuntu, the 'nova' user is now created as a system user, which
makes sense.
The 'nova' user created in the 'nova' class is not created as a system
user and is created before the 'nova-common' package is installed and
prevents the installation of the package.
So, require the package to be installed before puppet checks the user
existence and create the 'nova' user as a system user.
Signed-off-by: François Charlier <francois.charlier@enovance.com>
