add decode motion jpeg

[Archie1978]

Hello blackjack, good job for your driver.
I added in your code example http_streamer the code to decode JPEG. This will prevent the community GO from seeking compatibility.

kind regards, archie

[rgl]

You now have a decision to make, whether do merge this, or #31, or #40 (this does re-compress the mjpeg when the device already supports it) :-)