Truncate error source from start, not end, if it's too long to fit
Truncate error source from start, not end, if it's too long to fit

It's more helpful to see "...bar/baz.json" instead of "/long/path/to".

firepick1/jansson,liu3tao/jansson,firepick1/jansson,akheron/jansson-debian,chrullrich/jansson,slackner/jansson,firepick-delta/FireSight,markalanj/jansson,wirebirdlabs/featherweight-jansson,akheron/jansson,npmccallum/jansson,chrullrich/jansson,janetuk/jansson,yahoo/ygloo-external-jansson,akheron/jansson-debian,npmccallum/jansson,akheron/jansson-debian,akheron/jansson-debian,gameclosure/jansson,janetuk/jansson,gameclosure/jansson,Mephistophiles/jansson,slackner/jansson,AmesianX/jansson,liu3tao/jansson,firepick1/FireSight,Vorne/jansson,markalanj/jansson,simonfojtu/FireSight,rogerz/jansson,janetuk/jansson,yahoo/ygloo-external-jansson,AmesianX/jansson,simonfojtu/FireSight,janetuk/jansson,bstarynk/jansson,firepick1/FireSight,firepick1/FireSight,OlehKulykov/jansson,attie/jansson,Mephistophiles/jansson,OlehKulykov/jansson,attie/jansson,rogerz/jansson,firepick-delta/FireSight,gameclosure/jansson,simonfojtu/FireSight,bstarynk/jansson,rogerz/jansson,firepick-delta/FireSight,yahoo/ygloo-external-jansson,markalanj/jansson,Vorne/jansson,akheron/jansson,bstarynk/jansson,wirebirdlabs/featherweight-jansson,yahoo/ygloo-external-jansson,firepick1/jansson,akheron/jansson,rogerz/jansson