Improves clean to cleanup virsh nets and and other bridges

Improves clean to cleanup virsh nets and and other bridges

Currently only the admin and external bridges will be removed from the
jumphost which is only really clean for a baremetal deployment.  Virtual
deployments will leave br-tenant, br-api, br-storage.  This patch
removes those as well as deletes all Apex virsh networks from libvirt.

Also checks if authorized_keys exists before trying to edit it.

Change-Id: I1affe2733ba1dc38fd3b91fb14398454137f00a4
Signed-off-by: Tim Rozet <trozet@redhat.com>
(cherry picked from commit 02dc854a504569da15b0e41353a9f456e02599ad)