removing NOMATCH junkAOI from output

NOMATCH AOIs are put in to ensure that every frame has at least one AOI,
so that getCurrentAOIs don't return AOIs for distance matched AOIs.
Removing them from the actual log output.
tweaking the algorithm for gaze-video offset

- starting the video at 20sec; in some cases you find a mouse icon in
the video before mouse data in the gaze stream are recorded. So the
first sample would be a mismatch from later in the video. Skipping
forward to hopefully ensure we have both data.

- more robust estimate -- simply eliminating the top/bottom 4 time
difference estimates, rather than using all the data. This should help.
clean up logging
findVideoScalingFactor: tweaks

- made it more stringent, because in the case there are pop-up tools,
the corners may latch on to those. Tightened up the threshold.

- skipping 2 sec ahead if no corner match is found.