#2 Add whitespeck detection

[Klaas van Gend]

fruit flies and other small insects flying within, say, 1 meter of the camera will show up as flying white specks. This is a "false positive" - there's no-one in the room, but there is motion.

[Klaas van Gend]

changesets [0fa2a5] and [7a08d5] allow to actually save a stream without contours and time stamps. This enables saving more-or-less "raw" streams, which can be used for prototyping whitespec code.

[Klaas van Gend]

changeset [6a770e] reverts a bit, actually allowing to save things.
Now we have to wait until some fruit flies or light specs come along.

I tried to fake it using a flashlight - doesn't seem to work!

[Klaas van Gend]

changeset [24f3dd] allows running with custom config files.
changeset [5d4dfc] added such variable config file.
changeset [396033] adds the configurability to allow a custom amount of skipped frames.

All the infrastructure is now in place, I have demo files, I can parse them.