Add Host metadataedit

This functionality is in beta and is subject to change. The design and code is less mature than official GA features and is being provided as-is with no warranties. Beta features are not subject to the support SLA of official GA features.

The add_host_metadata processor annotates each event with relevant metadata from the host machine. The fields added to the event are looking as following:

      "ip": ["", ""],
      "mac": ["00:25:96:12:34:56", "72:00:06:ff:79:f1"]

The host information is refreshed every 5 minutes.