:refactor: renamed calibration_plot to calibration_curve
:fix: Calibration curve plotted correctly (transposed) in plot_calibration_plot.py
ENH Add histogram to calibration_plot example
ENH predicted probabilities can be optionally normalized in calibraton_curve
REFACTOR Polishing of plot_calibration.py example
COSMIT Rename plot_calibration_plot.py to plot_calibration_curve.py
COSMIT : Increased figure size in plot_calibration_curve.py
COSMIT Split joint figure in plot_calibration.py into two separate figures