get_os_info : wrangle OS and major version number in a semi-portable way
get_os_info : wrangle OS and major version number in a semi-portable way

twstrike/le_for_patching,TheBoegl/letsencrypt,TheBoegl/letsencrypt,dietsche/letsencrypt,letsencrypt/letsencrypt,xgin/letsencrypt,mrb/letsencrypt,bsmr-misc-forks/letsencrypt,mitnk/letsencrypt,lbeltrame/letsencrypt,thanatos/lets-encrypt-preview,stweil/letsencrypt,martindale/letsencrypt,lbeltrame/letsencrypt,mrb/letsencrypt,piru/letsencrypt,DavidGarciaCat/letsencrypt,thanatos/lets-encrypt-preview,DavidGarciaCat/letsencrypt,jtl999/certbot,kuba/letsencrypt,jsha/letsencrypt,martindale/letsencrypt,xgin/letsencrypt,jtl999/certbot,sjerdo/letsencrypt,wteiken/letsencrypt,lmcro/letsencrypt,twstrike/le_for_patching,mitnk/letsencrypt,dietsche/letsencrypt,Sveder/letsencrypt,goofwear/letsencrypt,VladimirTyrin/letsencrypt,stweil/letsencrypt,jsha/letsencrypt,goofwear/letsencrypt,Sveder/letsencrypt,piru/letsencrypt,letsencrypt/letsencrypt,brentdax/letsencrypt,VladimirTyrin/letsencrypt,wteiken/letsencrypt,brentdax/letsencrypt,kuba/letsencrypt,sjerdo/letsencrypt,lmcro/letsencrypt,bsmr-misc-forks/letsencrypt