Change log for 12-beta4.
Change log for 12-beta4.

- Amended changelog for 12-beta3 with translation update notice.

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