Remember annual consumption / price per kWh

[khdlr]

The "Wirtschaftlichkeit berechnen" dialogue resets every time it is opened. Would be nice to save this (not persistently, just during a single session)

cf. https://dresden.network/@carwe/113262266697849354

[FlorianK13]

I actually think we could have a new /results subpage open up. As soon as people have chosen their building, they usually are not interested in other buildings anymore. We could do a whole lot on this subpage then:

• Show graphs about our simulation (pv yield and consumption timeseries together with storage state of charge)

This is of course a lot more to do.

[FlorianK13]

However fixing the bug that the Wirtschaftlichkeit berechnen dialogue resets every time is a first fix as well :)