DashManifestRaw support, RequestExecutor support, http binary body and response support, spec version support, ignore unsupported sources, webm container preference in settings

Download estimations, codec in sources, wip plugin source request executor, setting to disable source deduplication (simplify sources), support for SlideUpItem descriptions, bigger SlideUpItems

added save button to non-saved local playlists

fixed exception failed to convert playlist job cancelled