UsageConfig: Latvian should be lav instead of lat

Thanks Artis

See: http://openpli.org/forums/topic/21339-automatic-language-subtitle-settings-improvements/page__st__40
configure.ac: simplify vu+ boxtype detection
MovieList: Add pictures to the known extensions

And do it slightly different - thanks DeBeek
MovieSelection: Remove delayTimer use callLater instead

As callLater does in fact the same
Merge remote-tracking branch 'openpli/master' into last