Added hist functions, cluster analysis and corresponding tests
Modified the Measurement class to extract Current Density(increasing and decreasing voltage cycle) values at a given Voltage potential. Added hist and hist_group functions in Postprocessing class to plot the distribution of Current Densities at a given voltage. Performed Cluster analysis in the Jupyter notebooks.
Added tests for function "interpolate_closest_values" in Utils class.
Edited by Markus Anthony Stricker