[sumo] higher quality stream URL

[AdamDaw]

> I'll have to try it full screen then.  I thought they had
> actually bumped up the resolution over the years, so I was
> disillusioned when I saw the small size (Looks like it's
> 160x120).  I can't complain since it's free.

> Thanks,
> Eric

They already tried with higher resolution (or someone was switching it
by mistake) for several days during Haru Basho this year. The stream
was starting in Makushita in 320x240, but unfortunately only for
few minutes. The picture looked like fullHD comparing to the one
we have now ;-) The first time I saw it I just couldn't believe my
eyes! It was SO beautiful... I still have a sample and I watched it
over a dozen times.

Kitakachiyama.