Use of P1-meter virtual devices for more specific monitoring

With use of P1-meter virtual devices it is now possible to separate lost energy both to full/empty battery and limitation of battery inverter. For explanation, please see the Wiki page.

Initial release of the simulated solar battery

In this release all current functionality is mature:

• Solar Battery energy level is monitored
• Limitations to solar battery inverters are taken into account
• Battery usage device shows both production and usage