Update beta message for 2.6.10beta.
Update beta message for 2.6.10beta.

0359xiaodong/SeriesGuide,epiphany27/SeriesGuide,UweTrottmann/SeriesGuide,r00t-user/SeriesGuide,UweTrottmann/SeriesGuide,hoanganhx86/SeriesGuide,artemnikitin/SeriesGuide