facilities: move to module

after the dc-cam class has been removed
facilities.pp is just PDU monitoring

first attempt was Ib06d7943e315c0 to move this
to nagios_common module, but per comments from Yuvi,
abandoned that and now creating a new module
'facilities' instead and moving it there

Change-Id: Ia41e114465b61eb9d6d6402a58131a4598f7eab2