Feat/54 new clust with beta merge

[arunge]

containes also https://github.com/Pandora-IsoMemo/iso-app/pull/124 which can be closed without merging

Version 23.03.6

New Features

• Adds mclust as new clustering option for KernelR and KernelTimeR (#54)
• Adds columns to excel for KernelTimeR: centroid full data, centroid sliced data, centroid temporal data

  Bug Fixes

• Unifies colors for clustering map and clustering plot within KernelTimeR (#108)
• Fixing crash in mapSim, mapDiff and kernel plotting function after updates regarding categorical target/dependent variable

[arunge]

@f-lukas I merged the changes from beta into your branch and fixed a bug because of NULL values in if-clauses of the plotting function (additionally I refactored the changes a bit in getZValues().) The bug comes from the changes regarding the categorical target/dependent variable. Feel free to review, test and merge your feature.

[arunge]

The tests should actually pass. With the last commit I only changed the news.md ... :shrug: