kWh/kWp running graph added

The running kWh/kWp graph is added to jSunnyReports 1.1beta8. This graphtype shows the running kWh/kWp yield for every day for a period of a year. The first year of data is not that valuable, after a year the graph gets valuable as it shows your annual yield in kWh/kWp and you can see a possible prognosis what your yield will be.