Add a cool dendrogram visualization

[diadochos]

Annotating intermediate nodes https://stackoverflow.com/questions/30317688/annotating-dendrogram-nodes-in-scipy-matplotlib

We shall import scipy only within the visualization function: https://stackoverflow.com/questions/3095071/in-python-what-happens-when-you-import-inside-of-a-function

Upside-down dendrograms: https://stackoverflow.com/questions/55291984/upside-down-branching-in-scipy-dendrogram

Dendrogram data structure: https://qiita.com/sho-matsuo/items/cd7f2b66e572bf60048b

https://stackoverflow.com/questions/43513698/relation-between-dendrogram-plot-coordinates-and-clusternodes-in-scipy/43519473#43519473

[diadochos]

• [x] Generate the correct hierarchy data of echelons.
• [x] Draw dendrogram (upside-down if possible)

[diadochos]

Maybe Phylograms?

https://github.com/biopython/biopython/blob/69a220ba4db4ebe998d10f15583ab0bacee1aa69/Bio/Phylo/_utils.py#L182

References

https://biopython.org/wiki/Phylo http://etetoolkit.org/ http://etetoolkit.org/docs/latest/tutorial/tutorial_drawing.html http://etetoolkit.org/docs/latest/index.html