Merge branch '27-far-and-frr-thresholds-are-computed-even-when-there-is-no-data-support' of https://gitlab.idiap.ch/bob/bob.measure into 27-far-and-frr-thresholds-are-computed-even-when-there-is-no-data-support

Conflicts:
	bob/measure/cpp/error.cpp
	bob/measure/plot.py
	bob/measure/test_error.py