SunEdison Inc (NYSE:SUNE) was up more than 9% in trading today (currently +7.9%) after Greenlight Capital’s David Einhorn talked it up during a talk at today’s Robin Hood Investor’s Conference, reports Julia La Roche at Business Insider, but considering this was already one of David Einhorn’s largest positions his comments shouldn’t have surprised anyone. David Einhorn was adding SUNE at a higher price earlier this year SunEdison Inc (NYSE:SUNE) may be the best performing solar stock of the year, but in this case looking at the aggregate return hides important details. At the end of June, Greenlight Capital owned 21…