Split out tmp clean and auto upgrades.

Create abstractions for tmpcleanup and automatic_upgrades
which can be used to install/include distro specific
modules modules for these features.

On Ubuntu this will still install unattended_upgrades and tmpreaper.

On RHEL we need to implement similar functionality and modules.

Change-Id: I9209610582e23c86dccb5e70691bb598dad36950
Reviewed-on: https://review.openstack.org/23197
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Clark Boylan <clark.boylan@gmail.com>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Approved: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins