prefer to use the sequence id over index
prefer to use the sequence id over index

when the sequence id exists and is short (less than int32 size) use -s
instead of -f.
this change is performed in order to simplify some live testing scripts.

kaltura/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module,kaltura/nginx-vod-module