WIP: I'm working on the initialisation of the particle filter.
Right now i'm searching throu all possible poses of the robot while
checking if the first image results in a high score. This takes very long.

I modified the picrating function, to use grayscale images. I need to
adapt the usual observe function to use grayscale images as well.

I also made changes inside the picrating function to discard (rating of 0.0)
particles, that have less then 10 projected points inside the image.
I made this decision while testing the initialisation, and still have to
look into the consequenses for the regular image observe.