Several issues with vuln commands

• vuln must be renamed to vulnerability
• bin/bob vuln epsc vuln_scores/{licit,spoof}/scores-{dev,eval} 's output is just a flat line.
• vuln hist examples are outdated.
• As requested in bob.measure#38 (closed), how can I produce the following figures: EPSC_IAPMR_w-cnn-motion-fusion.pdf EPSC_HTER_w-cnn-motion-fusion.pdf
• I don't think it's possible with bob vuln epsc command to get fig6 or fig9 of this paper: https://publidiap.idiap.ch/downloads//papers/2014/Chingovska_IEEETIFS_2014.pdf