Comment 2 for bug 797615

a Memoizer was implemented and now is in master, it caches _compute_lrem, we should implement tests on the Memoizer though

I'm also benchmarking and trying to find a possible solution about the slowness of plotting thousands of SVG(s) files, in particular the loop in __plot_single in CurvePlotter (openquake/output/curve.py) is a bottleneck. It writes slowly to the file-system and occupies 100% of one of my cpus