Modify the display of histograms: now can use subplots to display several histograms on one page, can no longer display both dev and eval histo at the same time, can control the number of columns in the legend

Add min-far-value option, rename -l (already used) to -Z, change the way linestyles are handled and make use of them optional

Replace a force_eval option so that no evaluation option is needed when evaluation scores are mandatory

Change the way the scores arguments are passed to the compute() function: it now does not rely on dev,eval pairs anymore and can take any number of different files (e.g. train)

Detailed option description, matplolib setting moved to callback functions, add vertical line option to DET

Various small changes after Amir review: add/remove command options, use matplotlib 2.2.2 functionalities, fix doc

move click options to bob.extension, change default axis for ROC and DET to be ISO conform, add command to generate fakes score files, add options to change title and axis labels

Change test -> eval, set different default tablefmt option, add and remove options, modify tests accordingly, and modify base MeasureBase class so that it can handle several dev/eval scores for each system (e.g. licit/spoofing for PAD)

Fix evaluate script (axes not set) and add defaults settings for the figure classes. Condensate options: list of axis limits instead of individual min/max per axis.

reshape code so that the figures can be re-used in other modules (class based plotting, add input loading function to read inputs files), split the code in different files (utils.py for utilities, figure.py for plotting related classes, commands.py for click commands). Change some click command defaults (nbins:  instead of 20, tablefmt:  instead of ), add click functionalities for a greater control of the plots (e.g. min/max axes values) and a nicer default visual. Fix the documentation and modify user guide according to the changes.