Modified logic so TimeSeekRange header will be included when seek format is time.  Also fixed issue in dlna_src_convert_npt_nanos_to_bytes() where time was left at nanoseconds not converted to seconds,
Added logic to track time seek events and not process the byte based version if already processed time seek.  Added some additional member variables to track related info.  Also if a time seek event is received but time seek is not supported by server, save time and convert to bytes when byte based seek event is received.  This is because the tsdemux estimate is not very accurate.
Got rid of a unnecessary log message.
Merge pull request #59 from cablelabs/include-time-seek-hdr

Modified logic so TimeSeekRange header will be included when seek format...