Fix tests on py26
Fix tests on py26

the print() function does not appear to be mockable there

dietsche/letsencrypt,DavidGarciaCat/letsencrypt,dietsche/letsencrypt,brentdax/letsencrypt,jtl999/certbot,mitnk/letsencrypt,lmcro/letsencrypt,stweil/letsencrypt,lmcro/letsencrypt,bsmr-misc-forks/letsencrypt,DavidGarciaCat/letsencrypt,mitnk/letsencrypt,letsencrypt/letsencrypt,bsmr-misc-forks/letsencrypt,wteiken/letsencrypt,stweil/letsencrypt,wteiken/letsencrypt,jsha/letsencrypt,jtl999/certbot,letsencrypt/letsencrypt,brentdax/letsencrypt,jsha/letsencrypt