Divik

- non-maintained scripts removed
- functions reorganized
- documentation extended

Stabilized `multiprocessing` and `dask` parallelization.

Enables more detailed KMeans logging and `dask` backend for bigger data.

- Introduce `OutlierSelector` that uses Huberta's outlier detection method to filter out the features with outlier characteristic (`OutlierAbundanceAndVarianceSelector`)
- Introduce `NoSelector` that allows to disable feature filtering in DiviK script
- Generalize output type of `DivikResult` to contain the `StatSelectorMixin` instead of `HighAbundanceAndVarianceSelector`