Rework Thumbnail defaultBackground to keep ratio.
Fix logic for generated tiles Thumbnail.
Another Tweak (regeszter patch)
Merge remote-tracking branch 'remotes/upstream/MP1-4090-Generation_Thumbnail_for_TV_Movie_based_on_lenght' into 1.4.0Fork_SEB_New_Master

Conflicts:
	mediaportal/Core/Util/Util.cs
	mediaportal/Core/Util/VideoThumbCreator.cs