hello_world with other files (unknown codec)

[FransM]

I used the hello executable on a recorded transport stream file.
It didn't work since the stream also contained EPG program guide data for which no codec was found.
As for the hello world example only the video stream is relevant it seems ok just to ignore streams for which no codec is found.
I've submitted #78 for this

[FransM]

pull request with the fix for this has been merged