Improvements and fixes

An inverter whose energy counter stalls no longer lowers a Fronius plant's energy, and editing a data logger no longer splits other loggers' inverter history.

• At Fronius plants, an inverter whose lifetime energy total stops advancing no longer lowers the plant's energy, its production being worked out from its power.
• Adding or editing a data logger no longer causes another logger's Huawei or Sungrow inverters to appear as new components with their history split.