Add option for reading InfluxDB passwd etc. from fixed local file
Switch to use FASER InfluxDB server. Account details is stored in /etc/faser-secrets.json, so on machines without that, the top.json file has to be changed to point to a non-pw protected file or not log to influxDB. File is currently only present on faser-daq-001/2.
Default is to log to test instance "DAQTestMetrics" rather than "DAQProdMetrics".