add "Running IOCs" field to instrument page

[rerpha]

I think this is an easy win as all you need to do is subscribe to
IN:INST:CS:BLOCKSERVER:IOCS, dehex and parse some JSON (we do this for the instlist already) then map it to a component.

make sure to create an interface for
A) the list of IOCs
B) the "IOC" object, which looks like this:

  "AEROFLEX_01": {
    "description": "Aeroflex Signal Generator",
    "running": false,
    "macros": [
      {
        "description": "Serial COM port",
        "pattern": "^COM[0-9]+$",
        "defaultValue": null,
        "hasDefault": "NO",
        "name": "PORT"
      },
      {
        "description": "Bus address e.g. GPIB address",
        "pattern": "^[0-9]+$",
        "defaultValue": "0",
        "hasDefault": "YES",
        "name": "BUS_ADDR"
      },
      {
        "description": "IP Address of prologix GPIB converter",
        "pattern": "^[0-9]+\\.[0-9]+\\.[0-9]+\\.[0-9]+$",
        "defaultValue": null,
        "hasDefault": "NO",
        "name": "PL_IPADDR"
      },
      {
        "description": "Type of Aeroflex",
        "pattern": "^(2023A|2030)$",
        "defaultValue": "2023A",
        "hasDefault": "YES",
        "name": "DEV_TYPE"
      }
    ],
    "pvsets": [],
    "pvs": []
  },

consider using something similar to the "Block" component where you have a basic
IOCNAME: RUNNINGSTATUS on first glance, but can expand to show the rest of the information.

[rerpha]

may need to use db server PV for same reasons as ISISComputingGroup/IBEX#8590