Optimizer: next steps

[andig]

It seems that core optimizer bugs have been resolved and it is- in its experimental state- already becoming useful. It would be nice to make some initial steps for actually using it by forecasting...:

• home battery full
• home battery empty
• home battery % at sunset
• home battery % at sunrise
• battery coverage for a given time range
• forecast vehicle charged (note this will diverge from the loadpoint preview since it takes solar into account)

If we start showing metrics like these on the main ui, we'll likely also discover more edge cases.