Improvements and fixes

An alarm or fault reported by an inverter now stays open until the inverter itself withdraws it. It no longer disappears from the list on its own.

• An alarm raised by a Huawei inverter no longer closes just because part of its alarm list could not be read.
• A fault reported by an inverter no longer closes on its own after the on-site data collection restarts.
• A low-insulation warning no longer stays shown as active after the inverter has withdrawn it.
• A battery unit read by a second data logger no longer keeps the make and model of the previous one.