Relax Autoconf version prereq
Relax Autoconf version prereq

From 2.63 to 2.59, which is more widely supported.

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