Parse incoming mpegts data to improve delay queue behavior

With srtsrc linked directly to the delay queue, I observed the
current-level-time metric go down while the current-level-bytes metric
went up. I suspect that the timestamp information from srtsrc is not
sufficient to be used as a basis for time-based buffering. Running the
data through tsparse first appears to fix this problem.

Author: chromakode

index.js

@@ -154,7 +154,7 @@ const pipelineMachine = Machine(
         }
 
         const pipeline = new gstreamer.Pipeline(`
-          srtsrc name=src uri=${srtInUri} ! ${delayQueue} ! tsdemux name=demux
+          srtsrc name=src uri=${srtInUri} ! tsparse ! ${delayQueue} ! tsdemux name=demux
           demux. ! queue ! video/x-h264 ! h264parse ! video/x-h264 ! avdec_h264 ! output-selector name=osel
           osel. ! queue ! isel.
           osel. ! queue