Add multiple counters for production and consumption of energy

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I added some support to the binaries to report consumption and production power for systems with PV modules, based on the BL0942 energy metering IC present in many smart plugs. This allows the device to be installed at the entry point of the house supply to accuratelly keep track of energy imported and exported, including runing automations to better maximize own consumption of PV generated energy.

At the moment there is only provision for one total counter. I know tasmota has one such feature, would this be buried somehow on the code for openbecken as well, or can we create a similar feature?

Thanks.