[Jamie, Vern, Duncan M]

I have modified the ODC-MASTER EPICS configuration to read guardian state information directly from the IFO top node, rather than the ISC_LOCK node.

This has no impact on the guardian system itself, but means that ODC-MASTER bit 3 is now a readback of H1:GRD-IFO_OK.

The upshot of all of this is that the ODC-MASTER will now not report 'observation ready' (bit 2) until all guardian nodes (monitored by the IFO node) report OK, and there are no test-point excitations on an ODC-monitored front-end.