+ * url The mandatory URL representing the media:
+ for plain file media - HTTP URL of this file,
+ for RTMP - RTMP URL,
+ for HLS - URL of the M3U8 media playlist,
+ for HDS - URL of the F4M manifest,
+ for DASH
+ - HTTP URL to plain file media (in case of
+ unfragmented media)
+ - URL of the MPD manifest or base URL
+ representing the media if MPD manifest
+ is parsed froma string (in case of
+ fragmented media)
+ for MSS - URL of the ISM manifest.