Adding Plotting API to PlottingFunctions in the eval tools

Summary

This MR introduces the following changes

• Adding draw_wps to histogram. Here you need to give the x-axis value where the vertical lines are plotted (Needed for the discriminant scores plots).
• Removing plotEfficiencyVariable, plotEfficiencyVariableComparison, FlatEfficiencyPerBin and plotFractionScan.
• Merging plotROCRatio and plotROCRatioComparison.
• Merging plot_score and plot_score_comparison.
• Merging plot_prob and plot_prob_comparison.
• Adapting plotting_umami.py to merged functions.
• Adapting plotting_umami.py examples for DL1r, DIPS and Umami to merged functions.
• Adapting unit tests to new merged functions.

Relates to the following issues

• #175 (closed) will be added in another MR
• #176 (closed) will be added in another MR

Conformity

• Changelog entry
• Documentation
• Development guidelines
• Style guides