Improvements and fixes

Solar plants no longer raise an alert every night that a device stopped sending. A curtailed inverter no longer reads as an outage.

• Inverters going quiet after dark no longer raise an alert at a solar plant, while a device that cannot be reached still alarms.
• An inverter held down to zero by the direct marketer no longer counts as an outage while its own status says it is limited.
• Huawei 33KTL-A and 36KTL inverters now show their real operating status and model instead of a wrong status code and their firmware.
• Inverters are no longer flagged as measuring wrongly when one stray reading invents energy on a quiet string.