Improvements and fixes

Phoenix Contact Power Control Unit 4.0 controllers now report their limits, and a curtailed plant no longer raises underperformance alerts.

• A Phoenix Contact Power Control Unit 4.0 now reports the grid operator's and direct marketer's limits and the setpoints given to the battery.
• Inverters at a plant held down by the grid operator or the direct marketer are no longer reported as producing far below expectation.
• A day on which half of a plant's components fall below expectation no longer raises an underperformance event on each of them.
• A Phoenix Contact controller whose web interface has no login can now be added without one.