Remove calls to KmeanOrder from notebook

[wleoncio]

The following Notebooks contain calls to the legacy function KmeanOrder():

• https://github.com/ocbe-uio/DIscBIO/blob/master/notebook/DIscBIO-CTCs-Notebook.ipynb
• https://github.com/ocbe-uio/DIscBIO/blob/master/notebook/DIscBIO-CTCs-Binder-Part1.ipynb
• https://github.com/ocbe-uio/DIscBIO/blob/master/notebook/DIscBIO-CTCs-Binder-Part3.ipynb

As per a warning on that function, KmeanOrder() has been replaced by pseudoTimeOrdering(), so all calls to KmeanOrder() should be replaced ASAP.

Ideally, just changing the name of the function called should suffice; if bugs occur, fixes should be made to pseudoTimeOrdering().

This change would allow us to remove KmeanOrder, thus reducing the code footprint and check time of the package (something DIscBIO is in need).