Implement different kind of normalization

[marabuuu]

Right now the normalization is done using the 99th percentile, but leads to a poor segmentation result when using crops. The amount of objects is in the cropped images is higher than in the usually used images, so the normalization (which works on percentiles) differs. Probably another way of normalization is needed for this.

[marabuuu]

Task:

• create a notebook with crop and whole image and normalize
• compare results of normalization (histogram ...)