Report machine status to ganglia

Add module and manifest to configure machine reports for ATLAS worker nodes using ganglia.  Reportst are made to the
central CERN ganglia server. Needs to be modified for belle.

Changes:
    new file: gce_node/manifests/ganglia.pp
    modified: gce_node/manifests/init.pp
    modified: gce_node/manifests/packages.pp