Adding undercloud ceilometer

-adding Undercloud Ceilometer that will collect statistics
 about Overcloud nodes, via SNMP

Change-Id: I1e90ad8d5bad16bc1c418ca2dbd78163abe6267c
Add passthrough configuration glue.

This provides a means for users to pass configuration through to the
machines they are deploying without us modelling that.

Change-Id: I7134eb0c6be2d5cb1795b2f03cfba4afb69dc837
blueprint: passthrough-config
Merge "Adding undercloud ceilometer"
Merge "Add passthrough configuration glue."
Merge remote-tracking branch 'upstream/master'