update skimage calls

[bertsky]

IMO in

page-segmentation/ocr4all_pixel_classifier/lib/dataset.py

Line 115 in e606774

return rescale(binary, scale,

there should be a conversion to uint8, because I get:

FutureWarning: Input image dtype is bool. Interpolation is not defined with bool data type. Please set order to 0 or explicitely cast input image to another data type. Starting from version 0.19 a ValueError will be raised instead of this warning.