Improvements and fixes

A network scan can now be limited to a subnet inside the plant's networks, and the monthly production chart keeps a slot for every day.

• The monthly production chart now keeps a bar slot for every day of the selected range, leaving days without data empty.
• A "Network scan" dialog now limits a scan to a subnet inside the plant's networks, and a device's type is picked from a fixed list.
• A changed peak power, self-consumption, location or commissioning date now reaches a plant's on-site agent by itself, and the "Core Data" page shows the update.
• The device search on a plant's "Networking" page now matches name, vendor, type, description, serial number, OS and MAC address as well as IP address.
• The plant image is now shown in 4:3, and the upload dialog previews exactly how it will be cropped.
• Adding an inverter or module type by hand no longer fails with an unexpected error.