Support fuzzy hashes in conjunction with image classification and clustering

[KilianB]

With 3.0.0 a matcher will be introduced which clusters hashes into similarity groups allowing to perform further matching based on the overall structure of the category.

The resulting cluster is mapped to a centroid and possibly an adapted (kd tree?). The hashes describing the clusters now are not entirely 0 or 1 but a value in between indicating the uncertainty of a specific bit in the hash.

[KilianB]

fixed with v 3.0.0